Category Archives: Research

“Frontiers of Digital Finance,” CEPR, 2025

CEPR eBook, 12 November 2025. PDF, HTML.

VoxEU column: Frontiers of Digital Finance: A Global Perspective. HTML.

VoxEU column: Frontiers of Digital Finance: Stablecoins, monetary ‘singleness’, tokenisation, and decentralised finance. HTML.

My introduction to/summary of the book:

The digitisation of payment, trading, and settlement systems is reshaping the financial architecture. New technologies are transforming how value is created, stored, transferred, and accounted for, altering the balance between public and private money, enabling the bundling of services, challenging traditional financial institutions, and prompting a wave of regulatory and institutional responses.

The global picture is uneven. Some regions are leapfrogging others, and conflicting ideologies about the proper role of the state in money give rise to fragmentation and concerns about monetary sovereignty.

This book offers an overview of major trends, as analysed by leading researchers and policymakers. It is structured in four parts. Part 1 presents regional perspectives, examining the approaches taken by India, Brazil, sub-Saharan Africa, the United States, and the euro area. For the euro area, the focus is on the digital euro and its implications for monetary sovereignty, privacy, and holding limits aimed at preserving financial stability.

Part 2 delves into stablecoins – the shooting stars in the digital financial ecosystem. Their evolution has spurred a flurry of policy debate, with the European Union’s Markets in Crypto-Assets Regulation (MiCAR) and the US GENIUS Act now offering greater regulatory clarity.

Part 3 turns to the concept of monetary ‘singleness’ – the principle that all forms of money in a currency area should be fully interchangeable and trade at par. As new digital forms of money proliferate, the cohesion of the monetary system may be called into question.

Part 4 brings together chapters on tokenisation, digital platforms, and decentralised finance (DeFi), and their broader impact on service bundling, credit allocation, financial inclusion, and consumer protection.

Regional perspectives

In the opening chapter of Part 1, Amiyatosh Purnanandam describes how India’s Unified Payments Interface (UPI), launched in 2016, has improved the efficiency of account-based payment systems by addressing the core frictions of information exchange, authentication, and final settlement. Developed under a public-private partnership, UPI enables real-time, low-cost, and interoperable digital payments between any two entities, regardless of their bank or payment service provider. India overcame challenges around identity verification and financial inclusion by implementing a nationwide system of digital, biometric-based identification and by expanding access to bank accounts for large segments of the unbanked population. These developments, alongside digital infrastructure investments and regulatory support for private sector participation, allowed UPI to lower transaction costs and provide small businesses with digital transaction histories that improved access to credit.

Purnanandam highlights how demonetisation and the COVID-19 pandemic accelerated the adoption of UPI. The system’s interoperable design allows users to choose among competing apps, reinforcing network effects and encouraging innovation. Early adoption by banks in some areas led to persistent increases in digital payment usage. Moreover, UPI has enabled streamlined welfare disbursements, with nearly 60% of subsidy payments being delivered directly into beneficiary accounts by 2024. According to Purnanandam, the UPI experience demonstrates the critical role of coordinated efforts across public and private sectors, along with a flexible and inclusive regulatory framework.

Fabio Araujo and Arnildo da Silva Correa describe the Central Bank of Brazil’s comprehensive innovation strategy, Agenda BC#, fostering tokenisation and integration to enable faster, more transparent, and programmable asset transfers. The agenda is built around four interlinked pillars: (1) Pix, an instant payment system launched in 2020, which also supports a ‘synthetic’ retail central bank digital currency (CBDC) model; (2) Open Finance, which promotes secure data sharing and competition; (3) Drex, Brazil’s central bank digital currency designed as a platform for a tokenised economy; and (4) the internationalisation of the Brazilian real, through regulatory modernisation and cross-border interoperability. Each component reinforces the others, creating a cohesive, digital financial ecosystem that enhances efficiency, security, innovation, and inclusivity.

Pix marked the foundational shift, offering a public infrastructure for instant, programmable payments that has been widely adopted across Brazil and credited with improving financial inclusion and spurring innovation. Open Finance expanded the ecosystem by allowing consumers to share financial data among institutions, unlocking more tailored services and competitive offerings. Drex builds on this by introducing distributed ledger technology, enabling advanced programmability, atomicity, and secure, tokenised deposits while incorporating privacy safeguards such as zero-knowledge proofs. Finally, internationalisation efforts are aligning domestic systems with global standards. Together, these initiatives aim to create a user-centric financial system where services are accessed through intelligent aggregators, enhanced by AI and driven by user-controlled data.

Luca Ricci and co-authors describe how digital innovations are reshaping the payment landscape across sub-Saharan Africa, facilitating financial inclusion, payment efficiency, lower remittance costs, and reduced informality. Private mobile money has been particularly impactful, with account ownership far outstripping the growth of traditional bank accounts. While central bank digital currencies, fast payment systems, and crypto assets are debated (with Nigeria having already launched the eNaira), their broader adoption is held back by weak digital infrastructure, limited institutional capacity, low levels of financial and digital literacy, and the high costs of system deployment. Cross-border payments remain slow and costly, and fragile governance frameworks heighten concerns about consumer protection, data privacy, and financial integrity.

To address these challenges, the authors outline four policy priorities: (1) investment in infrastructure and skills; (2) supporting private innovation within secure and competitive regulatory frameworks that enable interoperability and reinforce governance; (3) positioning public digital tools to complement – rather than compete with – private solutions, based on assessments of market gaps and resource needs; and (4) fostering regional and international coordination to ensure interoperability and resilience. Ultimately, digital payment reforms must be anchored in sound macroeconomic policies that preserve monetary sovereignty and financial stability.

Michael Lee argues that the 2025 Executive Order on digital financial technology and the GENIUS Act represent a strategic shift in the United States towards private sector-driven innovation in blockchain-based financial systems. The Executive Order rules out the development of a CBDC while endorsing a technology-neutral approach and regulatory clarity for stablecoins. The GENIUS Act establishes a federal framework for fiat-backed payment stablecoins, mandating at-par redemption, backing primarily by US dollar cash and cash equivalents, and regulatory oversight. Regarding the more than 340 stablecoins in circulation – 97% dollar-denominated and dominated by Tether and Circle – concerns remain over reserve transparency, and redemption practices vary widely.

Beyond stablecoins, Lee describes the increasing tokenisation of Treasury funds and commercial bank deposits. Tokenised US Treasury funds are largely held by long-term investors or used as on-chain reserves. Deposit tokens and tokenised deposits typically align with existing regulatory standards – including full know-your-customer (KYC)/anti-money laundering (AML) compliance and access via whitelisting – and can pay interest. In contrast, stablecoins circulate more freely (issuers functionally manage a whitelist only at the issuance stage) but are barred from offering interest directly under the GENIUS Act; however, issuers often partner with platforms to indirectly deliver yield. Together, these instruments form a spectrum, each balancing accessibility and return in different ways.

Ulrich Bindseil and Piero Cipollone argue that central bank electronic cash (CBEC) is essential to preserving monetary sovereignty, as private (often foreign) service providers increasingly dominate retail payments. This carries significant risks: rising payment costs due to oligopolistic market power, reduced financial and monetary stability, loss of seignorage income, and increased vulnerability to geopolitical risks. Bindseil and Cipollone present CBEC not as a disruption but as a necessary evolution to ensure the continued public provision of a neutral, secure, and sovereign monetary instrument that is designed to complement rather than replace commercial bank money.

The authors emphasise that monetary sovereignty faces new threats from globalisation, the advent of new technologies such as public blockchains, and a surge of nationalism that dismisses the merits of international co-operation. CBEC helps counter these threats across five dimensions: it protects macro-financial stability by preventing dollarisation; it ensures access to payment systems without abuse of market power; it preserves seigniorage income and the financial independence of central banks; it reduces strategic dependencies on foreign actors; and it protects informational sovereignty by avoiding overreliance on foreign-owned platforms.

Maarten van Oordt argues that the accelerating shift away from cash in the euro area is driving a significant erosion of privacy in payments. Unlike cash, electronic payments generate detailed records that are monitored by payment service providers and subjected to regulatory oversight. These data are not only used for compliance but also for commercial purposes, and they can be leveraged not just to monitor but also to censor or exclude individuals. The author emphasises that common justifications for payment surveillance – such as crime prevention and tax enforcement – do not automatically warrant broad monitoring powers in a democratic society.

Van Oordt does not expect the currently proposed digital euro design, which includes both online and offline payment options, to close the growing ‘privacy gap’ in retail payments. Online digital euro payments would be processed centrally, offering little improvement over existing systems, and, depending on the robustness of pseudonymisation techniques, could even exacerbate privacy risks. Offline payments, while potentially more private, face challenges such as usage limits and unresolved security concerns. Without critical amendments – such as enabling remote payments through offline balances or designing online payments to emulate the anonymity of cash – the author foresees the digital euro as heightening surveillance risks. He stresses that privacy in payments is a public good and warns that failing to safeguard it in the digital age would squander a crucial opportunity to redesign the financial system in such a way that upholds individual autonomy and democratic values.

Katrin Assenmacher and Oscar Soons explain that the European Commission’s June 2023 legislative proposal tasks the European Central Bank (ECB) with developing instruments to limit the use of the digital euro as a store of value, including the introduction of individual holding limits. These limits are intended to balance three objectives: enabling convenient payments; ensuring smooth monetary policy transmission; and safeguarding financial stability. The authors describe the ECB’s methodology for calibrating these limits so they are high enough for payment use but low enough to prevent significant bank deposit outflows that could destabilise funding structures.

To assess the appropriate holding limits, the ECB considers both a business-as-usual scenario – where the digital euro is mainly used for payments – and a flight-to-safety scenario, which involves mass withdrawals from banks during crises. Surveys and econometric analyses yield a broad range of estimates for digital euro demand. However, even under conservative assumptions, research indicates that large deposit outflows would likely only arise if individual holding limits exceeded €5,000, at which point banks would need to rely more heavily on central bank or market-based funding to manage liquidity pressures.

Stablecoins

In the first chapter of Part 2, Hugo van Buggenum, Hans Gersbach, and Sebastian Zelzner discuss how stablecoins – digital assets pegged to fiat currencies – have rapidly evolved from niche instruments into a major segment of digital finance. While fiat-backed stablecoins promise to combine the technological advantages of crypto with the stability of traditional money, depegging episodes underscore their vulnerability to run risks due to illiquid reserves, limited issuer commitment, and noisy market signals. Trading on active secondary markets can mitigate run incentives by giving holders alternative exit options when redemptions are restricted.

The authors discuss how the EU MiCA Regulation and the US GENIUS Act address systemic risks posed by stablecoins, focusing on reserve quality, redemption rights, and transparency. They suggest that well-designed redemption restrictions – such as gates or fees – should be permitted to prevent destabilising runs. They also caution against the remuneration of stablecoins, as interest payments could trigger destabilising competitive dynamics and coordination failures across issuers, and examine potential effects on banks, monetary policy transmission, and overall financial stability.

Rodney Garratt highlights the dramatic growth of the US dollar-denominated stablecoin market and the fundamental regulatory shift that now encourages institutional participation, including by commercial banks. The author expects the entry of traditional financial institutions to reshape the competitive landscape, with banks serving their regulated clients via public blockchain-based payment rails, while existing issuers continue to operate within the crypto ecosystem.

Garratt likens stablecoins to digital travellers’ cheques – clearing instruments redeemable at par but not tied to individual account holders. As banks enter the space, redemption frictions and interoperability challenges echo historical issues from the pre-clearinghouse era of cheque processing. He argues that a universal stablecoin clearing system will be crucial for broader adoption, ensuring fungibility and monetary singleness across issuers. While stablecoins may not offer clear advantages in many domestic use cases – given the rise of real-time payment systems – he sees potential in global, programmable transactions, particularly for corporate users needing low-cost, high-speed, cross-border payments. Garratt predicts bank-issued stablecoins will have short lifecycles, acting as temporary payment instruments rather than long-term stores of value.

Steve Cecchetti and Kermit Schoenholtz compare stablecoins and tokenised deposits within the context of the new US regulatory framework. They note that although the GENIUS Act prohibits interest payments to holders, limits eligible reserve assets, and enforces compliance with KYC, AML, and anti-terrorist financing (ATF) standards, it still contains significant regulatory gaps. Platforms can circumvent the interest ban by offering yield-like ‘rewards’; reserve requirements permit exposure to run-prone assets like prime money market funds and uninsured bank deposits; and enforcing illicit-use restrictions is particularly challenging for users of noncustodial wallets. Most notably, the absence of capital requirements raises doubts about the ability of stablecoins to serve as safe, information-insensitive assets under stress.

According to the authors, tokenised bank deposits offer a more stable and robust alternative, combining the legal protections of traditional bank deposits with features such as programmable settlement, real-time clearing, and blockchain interoperability. Because they are issued by regulated, FDIC-insured banks with central bank access, tokenised deposits are shielded from many of the structural vulnerabilities that afflict stablecoins. Moreover, they offer stronger privacy protections, reduce cross-border redemption risks, and more easily support multiple currencies – mitigating concerns around dollar dominance.

David Andolfatto explores the role of Tether (USDT) in the evolving landscape of private digital money, highlighting both its utility and its vulnerabilities. Pegged to the US dollar while operating outside the traditional banking system, Tether fills critical roles in blockchain-based asset trading, cross-border payments, and as a dollar substitute in emerging markets. While verified institutional users are entitled to par redemption, retail users depend on secondary market liquidity. This two-tier structure and the absence of regulatory oversight raise financial stability concerns.

Despite claims of full reserve backing, primarily in short-term US Treasuries, Tether’s transparency is limited to attestations, and it is legally structured to avoid US regulation. But Andolfatto argues that Tether’s reliance on Cantor Fitzgerald, a US-regulated primary dealer, presents a policy window for oversight and systemic risk mitigation. In particular, US policymakers could require Cantor to act as a fiduciary, using its Federal Reserve master account to tighten reserve management, and applying existing AML/KYC standards.

Richard Portes argues that the multi-issuer stablecoin model (MISC), where a stablecoin is issued jointly by EU-regulated institutions and third-country entities, presents serious financial stability risks and regulatory challenges. This arrangement, not explicitly foreseen under the MiCA regulation, creates loopholes for regulatory arbitrage, fragmented reserve management, and accountability confusion, particularly during redemption runs or crises. The fungibility of tokens across jurisdictions allows issuers and holders to treat them as interchangeable, even though only part of the system is subject to EU rules, reserves may be ringfenced abroad during stress, and redemptions could be unequally honoured.

Portes sees several policy options, including banning MISCs outright, amending MiCA to explicitly regulate cross-jurisdiction co-issuance, or developing global regulatory standards. He notes that some EU policymakers have voiced strong opposition to MISCs, and warns that regardless of the legislative path chosen, urgent supervisory and legal adaptations are needed to preserve financial stability, close regulatory gaps, and uphold MiCA’s credibility in a globalised crypto-financial system.

Harald Uhlig compares European plans for a CBDC and the US strategy to promote privately issued stablecoins. While the ECB sees CBDC as a way to modernise cash, preserve monetary sovereignty, and reduce dependence on foreign payment providers, the US approach possibly reflects stronger trust in markets and concerns about government overreach and privacy. Despite these different strategies, the author notes a fundamental convergence: both digital currencies must avoid paying interest and may ultimately rely on central bank backing to ensure safety and stability.

Uhlig is critical of the US regulatory framework that prevents stablecoins from becoming robust and competitive – particularly the denial of Federal Reserve master accounts and interest payments, which would allow them to operate like fully reserved narrow banks. He warns that this creates stablecoins that are ‘fragile by design’, as illustrated by recent depegging events. He also highlights the inconsistency of paying interest on bank reserves but not on digital cash held by the public, viewing it as a concession to the traditional banking sector. While stablecoins may offer innovative features like smart contracts and programmable payments, their growth could generate international tensions. Ultimately, Uhlig sees stablecoins and CBDCs as part of ongoing creative destruction in finance – technological progress that doesn’t eliminate but instead relocates deeper structural tensions like liquidity risk and maturity mismatches.

Monetary singleness

In the first chapter of Part 3, Rhys Bidder explores the principle of singleness of money – the idea that all forms of money within a currency area, including bank deposits and digital tokens, should trade at par with the central bank’s unit of account. In the traditional two-tier banking system, singleness is maintained through central bank infrastructure and liquidity support, ensuring trust and stability. In contrast, stablecoins and DeFi instruments operate outside these systems, making minor deviations from par common.

Bidder argues that these small fluctuations are not inherently problematic and may fade as technology, transparency, and market infrastructure improve. The real concern lies in large depegs during periods of stress, such as during the 2023 US banking crisis, which exposed the fragility of stablecoins under liquidity pressure. To address this, he proposes that stablecoins backed by high-quality assets be granted conditional access to emergency liquidity facilities. Rather than fixating on minor price noise, the policy debate should focus on preventing systemic instability during times of stress.

Jonathan Chiu and Cyril Monnet similarly examine the concept of monetary singleness. Their starting point is the common concern among central banks that programmable digital currencies – whose use can be restricted through embedded rules – could undermine singleness by creating distinctions among tokens of equal face value. This concern has led central banks to dismiss digital currencies incorporating programmability. In contrast, the authors argue that programmability can enhance economic efficiency and that the loss of singleness may be an acceptable – or even desirable – feature in certain contexts.

Chiu and Monnet observe that, under perfect information, token prices would adjust to reflect differences in restrictions, enabling efficient allocations despite the loss of singleness. In such cases, prohibiting programmability would reduce welfare. However, under imperfect information, adverse selection may arise, with unrestricted tokens effectively subsidising restricted ones. As these distortions grow, the welfare gains from programmability diminish. The authors challenge the conventional view – often informed by the US free banking era – that non-uniform money necessarily leads to inefficiency. Instead, they advocate for a nuanced regulatory approach, such as Pigouvian taxes on excessive programmability or incentives to enhance token transparency.

Tokenisation, platforms, credit, and decentralised finance

In the first chapter of Part 4, Jon Frost, Leonardo Gambacorta, Anneke Kosse, and Peter Wierts argue that tokenisation – the digital representation of assets on programmable platforms – has the potential to improve the efficiency and functionality of the financial system. The tokenisation of money, including central bank money and commercial bank deposits, could be a first step, while stablecoins fall short in the authors’ eyes on stability, liquidity, and regulatory compliance. They suggest building on the existing two-tier monetary system and integrating tokenisation with central bank money to ensure trust and safety.

The authors also see potential for tokenisation to enhance capital markets – particularly in bond issuance – by reducing costs and improving liquidity. However, they also point to risks stemming from legal uncertainty, operational vulnerabilities, and the concentration of multiple functions on single platforms. Governance challenges and poor interoperability with legacy systems further complicate adoption. In the authors’ view, both public and private sectors have roles to play in managing these risks and enabling tokenisation to contribute meaningfully to financial safety and efficiency.

Emre Ozdenoren and Kathy Yuan explore how tokenised money – digital currencies issued or guaranteed by central banks or private platforms – can transform financial systems by automating transactions, reducing information frictions, and enhancing liquidity. Unlike traditional digital payment instruments, tokenised money incorporates smart contracts, enabling automatic enforcement of contractual terms without intermediaries. It serves a dual function as both a payment method and a collateral asset for financial contracts, offering greater efficiency, security, and traceability. Its programmability reduces human error, minimises fraud, and lowers custodial and settlement costs, particularly in complex financial transactions involving future obligations.

Ozdenoren and Yuan describe how tokenised money acts as a collateral multiplier, expanding the supply of secure and transparent assets while reducing reliance on sovereign bonds – thereby mitigating systemic risks such as the ‘dash for cash’ or the sovereign-financial doom loop. Tokenisation also enables the creation of secondary markets, closely integrating funding and market liquidity. While it introduces new risks, including cybersecurity threats and novel financial vulnerabilities, its potential benefits – and seigniorage opportunities for issuers – position tokenised money as a foundational element of future financial infrastructure.

Markus Brunnermeier and Jonathan Payne similarly stress the role of digital payment ledgers in offering a powerful new mechanism to expand access to credit by embedding repayment directly into digital transaction systems. Turning future revenues into ‘digital collateral’, these systems promise to relax borrowing constraints, but their potential is shaped less by technology than by institutional design and confronts a trilemma: no arrangement can simultaneously ensure strong enforcement, limit private rent extraction, and preserve user privacy. According to the authors, this trilemma lies at the heart of the evolving financial architecture.

Brunnermeier and Payne compare three institutional approaches. The first is BigTech platforms, which can enforce repayment by controlling trade and payment flows, using proprietary tokens and internal ledgers, but create risks of monopoly power and privacy loss. The second is public options – from basic infrastructure like FedNow to full programmable CBDCs – that can serve as inclusive, transparent alternatives, but may weaken enforcement or require trade-offs on privacy. The third approach is regulatory ‘co-opetition’ between platforms, which encourages enforcement through shared data and coordinated default tracking, while using competition to suppress rents. All these models face technical and governance complexities, particularly in enforcing privacy and limiting systemic risk. The authors conclude that, ultimately, expanding access to credit through digital payment systems demands a nuanced balance across enforcement, rent extraction, and privacy.

Wenqian Huang describes how DeFi is transforming financial infrastructure by enabling trading and lending without traditional intermediaries. At the core of this system are decentralised exchanges and lending protocols that use smart contracts to automate market functions. Decentralised exchanges replace order books with pooled liquidity and algorithmic pricing, enabling large trades with minimal price dislocation for near-par instruments like stablecoins. DeFi lending protocols mimic collateralised finance by letting users borrow against tokenised assets, with automatic margin calls enforced by code. These innovations are now expanding into real-world asset markets, such as tokenised real estate.

Huang argues that the integration of DeFi mechanisms into tokenised real-world asset markets offers efficiency gains but also introduces risks. As DeFi becomes increasingly intertwined with fiat systems and real assets, the challenge for regulators is to craft oversight that acknowledges decentralisation while mitigating systemic risk. Ultimately, DeFi’s contribution may not lie in replacing existing institutions but in reshaping our understanding of resilient and efficient market design.

Claudio Tebaldi argues that digital adoption, rising incomes, and growing global interest have brought a younger, more diverse cohort of retail investors into financial markets. While these investors now access a broad range of complex financial products, their financial literacy is often low and their understanding of product risks inadequate. De facto, digital innovation brings with it a form of technology-driven deregulation, and finding the right balance between fostering innovation and protecting retail investors is difficult. While some regulatory environments, such as that of the European Union, emphasise consumer protection through rules and oversight, they often limit scalability and participation, raising concerns about accessibility and innovation. In some cases, platform design – rather than regulation – bears the burden of educating and guiding users.

Tebaldi proposes a regulatory framework that balances the goals of consumer protection, large-scale participation, and inclusive stakeholder governance. He argues that AI-powered robo-advisory tools offer promise in bridging the education gap at scale. To improve governance, token issuers should meet governance standards comparable to those common in traditional finance.

“CBDC and Monetary Architecture,” UniBe DP, 2025

UniBe VWI Discussion Paper 25-09, October 2025. PDF.

We review the macroeconomic literature on retail central bank digital currency (CBDC), organizing the discussion around a CBDC-irrelevance result. We identify both fundamental and policy-related sources of relevance, or departures from neutrality. Bank disintermediation—the crowding out of deposits—does not, by itself, constitute such a source. We argue that the literature has primarily focused on policy-related sources of non-neutrality, often without making this focus explicit. From a macroeconomic perspective, CBDC is, at its core, a matter of monetary architecture, and political economy considerations are central to understanding CBDC policy design.

“A Tractable Model of Epidemic Control and Equilibrium Dynamics”, JEDC, 2025

With Martín Gonzalez-Eiras. Journal of Economic Dynamics and Control 178, 105145. September 2025. PDF, PDF of appendices C, D, E.

We develop a single-state model of epidemic control and equilibrium dynamics, and we show that its simplicity comes at very low cost during the early phase of an epidemic. Novel analytical results concern the continuity of the policy function; the reversal from lockdown to stimulus policies; and the relaxation of optimal lockdowns when testing is feasible. The model’s enhanced computational efficiency over SIR-based frameworks allows for the quantitative assessment of various new scenarios and specifications. Calibrated to reflect the COVID-19 pandemic, the model predicts an optimal initial activity reduction of 38 percent, with subsequent stimulus measures accounting for one-third of the welfare gains from optimal government intervention. The threat of recurrent infection waves makes the optimal lockdown more stringent, while a linear or near-linear activity-infection nexus, or strong consumption smoothing needs, reduce its stringency.

“Pricing Liquidity Support: A PLB for Switzerland”, CEPR DP, 2025

With Cyril Monnet and Remo Taudien. CEPR Discussion Paper 20309, May 2025. PDF.

The proposed revision of the Swiss Banking Act introduces a public liquidity backstop (PLB) for distressed systemically important banks (SIBs), in part to facilitate resolution. We examine the impact of the PLB on fiscal balances, welfare, and the incentives of bank shareholders and management. A PLB, like too-big-to-fail (TBTF) status, acts as a subsidy for non-convertible bonds, which can create negative externalities. Corrective measures should be implemented before the PLB is activated to align incentives with societal interests. We conservatively estimate that UBS Group’s TBTF status results in funding cost reductions of at least USD 2.9 billion in 2022. The risk for Switzerland of hosting SIBs warrants additional precautionary savings.

“Pricing Liquidity Support: A PLB for Switzerland”, UniBe DP, 2025

With Cyril Monnet and Remo Taudien. University of Bern Discussion Paper 25.01, January 2025. PDF.

The proposed revision of the Swiss Banking Act introduces a public liquidity backstop (PLB) for distressed systemically important banks (SIBs), in part to facilitate resolution. We examine the impact of the PLB on fiscal balances, societal welfare, and the incentives of bank shareholders and management. A PLB, like too-big-to-fail (TBTF) status, acts as a subsidy for non-convertible bonds, which can create negative externalities. Corrective measures must be implemented before the PLB is activated to align incentives with societal interests. We conservatively estimate that Swiss SIBs’ TBTF status results in funding cost reductions far greater than the proposed ex-ante compensation, with UBS Group AG alone gaining at least USD 2.9 billion in 2022. The risk for Switzerland of hosting SIBs warrants additional precautionary savings.

“Money and Banking with Reserves and CBDC,” JF, 2024

Journal of Finance. HTML (local copy).

Abstract:

We analyze the role of retail central bank digital currency (CBDC) and reserves when banks exert deposit market power and liquidity transformation entails externalities. Optimal monetary architecture minimizes the social costs of liquidity provision and optimal monetary policy follows modified Friedman rules. Interest rates on reserves and CBDC should differ. Calibrations robustly suggest that CBDC provides liquidity more efficiently than deposits unless the central bank must refinance banks and this is very costly. Accordingly, the optimal share of CBDC in payments tends to exceed that of deposits.

“Money and Banking with Reserves and CBDC,” CEPR, 2023

CEPR Discussion Paper 18444, September 2023. HTML (local copy).

Abstract:

We analyze the role of retail central bank digital currency (CBDC) and reserves when banks exert deposit market power and liquidity transformation entails externalities. Optimal monetary architecture minimizes the social costs of liquidity provision and optimal monetary policy follows modified Friedman (1969) rules. Interest rates on reserves and CBDC should differ. Calibrations robustly suggest that CBDC provides liquidity more efficiently than deposits unless the central bank must refinance banks and this is very costly. Accordingly, the optimal share of CBDC in payments tends to exceed that of deposits.

“Payments and Prices,” CEPR/SNB, 2023

CEPR Discussion Paper 18291 and SNB Working Paper 3/2023, July 2023. HTML, PDF (local copy CEPR, local copy SNB).

We analyze the effect of structural change in the payment sector and of monetary policy on prices. Means of payment are obtained through portfolio choices and commodity sales and “liquified” through velocity choices. Interest rates, intermediation margins, and costs of payment instrument use affect portfolios, velocities, liquidity, relative prices, and the aggregate price level. Money is neutral, interest rate policy is not. Scarcer liquidity need not drive up velocity. Payment instruments and velocities generate positive externalities. Commodity price aggregates mis-measure consumer price inflation, distinctly so over the business cycle.

“Digital Euro: An Assessment of the First Two Progress Reports,” SUERF, 2023

SUERF Policy Brief 612, June 2023. HTML, PDF.

Executive summary:

The ECB’s first two progress reports on the digital euro clarify the project teams’ considerations. Some motivations for a digital euro remain vague, some fundamental tradeoffs receive limited attention. Most importantly, the reports lack an analysis of why digital euro holdings as stores of value are not desirable and whether strategies to limit such holdings cause collateral damage. Against that backdrop some of the design choices backed by the Governing Council appear premature.

“Digital Euro: An Assessment of the First Two Progress Reports,” European Parliament, 2023

European Parliament, April 2023. PDF.

Executive summary:

The two progress reports provide an insightful overview over some of the thinking underlying the digital euro project. The reports remain vague in some respects, which is not surprising given the early stage of the project and the division of tasks between the ECB and the Commission.

The first report suggests that the digital euro can help preserve public money as the anchor of the payment system, but it does not explain how the decline in cash use endangers the anchor role or how a digital euro would mitigate the associated risks. It motivates the digital euro as contributing to Europe’s strategic autonomy, but does not clarify whether the autonomy concerns national security, cheaper payment services, or monetary sovereignty, and why either of these would suggest a focus on consumers rather than business users. More generally, the report discusses few economic motives for a digital euro in depth and this raises doubts about the proper sequencing of design choices. Some arguments for privacy restrictions are not fully convincing. The most important shortcoming of the first report is the lack of analysis of why digital euro holdings as stores of value are not desirable (or why this issue is beyond discussion) and whether strategies to limit such holdings cause collateral damage.

The second report lacks a discussion of incentive compatibility of the envisioned public-private partnership model. It also lacks detail on the proposed settlement, funding and defunding models and on the incidence of the payment scheme’s costs.

The reports do not discuss implications for central bank balance sheets, interest rates, political interference, and the ECB’s mandate to introduce a digital euro.

My colleague Cyril Monnet also wrote a report (PDF). His executive summary:

Since Facebook’s announcement of Libra in July 2019, central banks, including the European Central Bank (ECB), have accelerated investigations on the introduction of their own retail digital currency.

This study analyses the two reports published by the ECB regarding its investigation for the introduction of a digital euro.

The digital euro can offer many advantages over existing means of payment. However, most of these benefits, as outlined in the two reports, are of a systemic and social nature, rather than being benefits for users.

A broad acceptance and usage of the digital euro requires that it brings benefits not only to consumers but also to merchants. The digital euro needs a platform business model that brings consumers but also incentivises merchants to adopt it.

In addition, considering the social benefits it brings, the ECB should design the digital euro to promote its appeal. The ECB should consider eliminating holding limits and discontinuing penalising remuneration schemes as soon as possible after its introduction. Also, the ECB should consider adding some programmability features to the digital euro.

There are also some challenges ahead.

The deployment of the digital euro by regulated intermediaries results in a conflict of interest, as the digital euro competes with a significant source of their revenue, i.e. payments. To restrict the fees charged to users of the digital euro by intermediaries, the ECB should consider implementing a transparent fee structure that may incorporate subsidies.

Also, while consumers use cash to preserve their anonymity, the digital euro will always leave a data trail. It is therefore key that the future design of the digital euro preserves at least the privacy of its users, which may require the central bank to make compromises with some other objectives.

It is not clear that distributed ledger technology (DLT) is the best way to deploy the digital euro but making it DLT compatible and programmable can foster innovations in decentralised finance.

Update, late May 2023: Christian Hofmann also wrote a report (PDF). His executive summary:

… This paper argues that the paramount reason for introducing a digital euro should lie in the imperfections of the existing money landscape that offers the public suboptimal choices for store of value and payment transactions. In that respect, the introduction of a digital euro holds great promise for the public, and this paper focuses on one of the most essential design features of a digital euro. The European Central Bank (ECB) plans to introduce a limited version of a digital euro that would cap the maximum amounts of digital euros that individuals can hold, but this paper challenges the ECB’s assumption that such caps are needed in the interest of financial stability. The concerns voiced by the ECB and other central banks about the risks from sudden outflows of liquidity from bank deposits to CBDC are realistic, but this paper argues that these risks are manageable and that a digital euro might even support financial stability in a banking crisis. Properly implemented, an unlimited digital euro would allow central banks and other authorities to wield control more effectively during bank run scenarios and improve their overall ability to manage crises situations. 

The Economist on CBDC—and SVB

The Economist refers to our work in the `Free Exchange’ section:

But some argue banks would work fine if the public switched their deposits for central-bank digital currencies, so long as the central bank stepped in to replace the lost funding. “The issuance of [such currencies] would simply render the central bank’s implicit lender-of-last-resort guarantee explicit,” wrote Markus Brunnermeier and Dirk Niepelt in 2019. This scenario seems to have partly materialised since the failure of svb, as deposits have fled small banks for money-market funds which can park cash at the Fed, while the Fed makes loans to banks.

“Sovereign Bond Prices, Haircuts and Maturity,” JIE, 2023

With Tamon Asonuma and Romain Ranciere. Journal of International Economics 140, 103689, January 2023. PDF.

We document that creditor losses (”haircuts”) during sovereign debt restructurings vary across debt maturity. In our novel dataset on instrument-specific haircuts suffered by private creditors in 1999-‒2020 we find larger losses on short- than long-term debt, independently of the specific haircut measure we use. A standard asset pricing model rationalizes our findings under two assumptions, both of which are satisfied in the data: increasing short-run restructuring risk in the run-up to a restructuring, and high exit yields. We relate our findings to the policy debate on restructuring procedures.

“Sovereign Bond Prices, Haircuts and Maturity,” UniBe, 2022

With Tamon Asonuma and Romain Ranciere. UniBe Discussion Paper 22-13, November 2022. PDF.

We document that creditor losses (”haircuts”) during sovereign debt restructurings vary across debt maturity. In our novel dataset on instrument-specific haircuts suffered by private creditors in 1999-‒2020 we find larger losses on short- than long-term debt, independently of the specific haircut measure we use. A standard asset pricing model rationalizes our findings under two assumptions, both of which are satisfied in the data: increasing short-run restructuring risk in the run-up to a restructuring, and high exit yields. We relate our findings to the policy debate on restructuring procedures.

“Money and Banking with Reserves and CBDC,” UniBe, 2022

UniBe Discussion Paper 22-12, October 2022. PDF.

We analyze retail central bank digital currency (CBDC) in a two-tier monetary system with bank deposit market power and externalities from liquidity transformation. Resource costs of liquidity provision determine the optimal monetary architecture and modified Friedman (1969) rules the optimal monetary policy. Optimal interest rates on reserves and CBDC differ. A calibration for the U.S. suggests a weak case for CBDC in the baseline but a much clearer case when too-big-to-fail banks, tax distortions or instrument restrictions are present. Depending on central bank choices CBDC raises U.S. bank funding costs by up to 1.5 percent of GDP.

“The Political Economy of Early COVID-19 Interventions in US States,” JEDC, 2022

Journal of Economic Dynamics and Control, July 2022, with Martin Gonzalez-Eiras. PDF (local copy).

We investigate how politico-economic factors shaped government responses to the spread of COVID-19. Our simple framework uses epidemiological, economic and politico-economic arguments. Confronting the theory with US state level data we find strong evidence for partisanship even when we control for fundamentals including the electorate’s political views. Moreover, we detect an important role for the proximity of elections which we interpret as indicative of career concerns. Finally, we find suggestive evidence for complementarities between voluntary activity reductions and government imposed restrictions.

“The Political Economy of Early COVID-19 Interventions in US States,” CEPR, 2022

CEPR Discussion Paper 16906, January 2022, with Martin Gonzalez-Eiras. PDF (local copy).

We investigate how politico-economic factors shaped government responses to the spread of COVID-19. Our simple framework uses epidemiological, economic and politico-economic arguments. Confronting the theory with US state level data we find strong evidence for partisanship even when we control for fundamentals including the electorate’s political views. Moreover, we detect an important role for the proximity of elections which we interpret as indicative of career concerns. Finally, we find suggestive evidence for complementarities between voluntary activity reductions and government imposed restrictions.

Forthcoming in the JEDC.

“Reserves for All: Political Rather Than Macroeconomic Risks,” CEPR, 2021

Chapter 5 in the CEPR eBook, November 24, 2021. HTML.

From the conclusion:

From a macroeconomic perspective, central banks can largely neutralise the consequences of CBDC. What is highly uncertain, however, is whether they would choose to do so – the political risks of ‘Reserves for All’ are first-order. The decision for or against CBDC thus should not only reflect the assessment of economic trade-offs, but also whether societies are confident in their ability to efficiently manage conflicts of interest. If not, and if they fear that the introduction of CBDC could further politicise banking and central banking, then the introduction of CBDC might constitute a risky regime change. It will be interesting to see how different [countries] judge this risk.

“CBDC: Considerations, Projects, Outlook,” CEPR/VoxEU, 2021

CEPR eBook, November 24, 2021. HTML.

VoxEU, November 24, 2021. HTML.

Retail central bank digital currency has morphed from an obscure fascination of technophiles and monetary theorists into a major preoccupation of central bankers. Pilot projects abound and research on the topic has exploded as private sector initiatives such as Libra/Diem have focused policymakers’ minds and taken the status quo option off the table. In this eBook, academics and policymakers review what we know about the economic, legal, and political implications of CBDC, discuss current projects, and look ahead.

“Austerity,” EJ, 2021

Economic Journal, February 2021, with Harris Dellas. PDF.

We study the optimal debt and investment decisions of a sovereign with private information. The separating equilibrium is characterised by a cap on the current account. A sovereign repays debt amount due that exceeds default costs in order to signal creditworthiness and smooth consumption. Accepting funding conditional on investment/reforms relaxes borrowing constraints, even when investment does not create collateral, but it depresses current consumption. The model contains the signalling elements emphasised by creditors in the Greek austerity programmes and is consistent with the reduction in the loans issued by Greece and their interest rate following the 2015 election.

“Money Creation, Bank Profits, and CBDC,” VoxEU, 2021

VoxEU, February 5, 2021. HTML.

Based on CEPR DP 15457, I assess possible implications of the introduction of retail CBDC for bank profits. The model implies annual implicit subsidies to U.S. banks of up to 0.8 percent of GDP during the period 1999-2017.

Comments on Geneva Report 23

Panel with Elga Bartsch, Agnès Bénassy-Quéré, Giancarlo Corsetti, Olivier Garnier, and Charles Wyplosz. Moderated by Tobias Broer.

Elga Bartsch, Agnès Bénassy-Quéré, Giancarlo Corsetti, Xavier Debrun: Geneva Report 23 | It’s All in the Mix: How Monetary and Fiscal policies Can Work or Fail Together.

Event at PSE.

My comments on the report.

“The Pandemic Endgame,” VoxEU, 2021

VoxEU, January 11, 2021, with Martin Gonzalez-Eiras. HTML.

Based on the CEPR discussion paper, we draw conclusions for the pandemic endgame. We explain why Israel will likely impose a harsher lockdown than other countries, especially poor ones. And why we should expect “inverse lockdowns”—measures to stimulate social interaction.

Reading List on ‘Free’ or ‘Not-so-free’ Public Debt

Risk, Discounting, and Dynamic Efficiency

In the presence of risk, a comparison of the risk-free interest rate and the expected growth rate is insufficient to assess whether an economy is dynamically efficient or inefficient. Stochastic discount factors—not risk-free interest rates—enter the government’s budget constraint, even if debt is safe.

These points are made, for example, by Andrew Abel, N. Gregory Mankiw, Lawrence Summers, and Richard Zeckhauser (Assessing Dynamic Efficiency: Theory and Evidence, REStud 56(1), 1989),

the issue of dynamic efficiency can be resolved by comparing the level of investment with the cash flows generated by production after the payment of wages … dynamic efficiency cannot be assessed by comparing the safe rate of interest and the average growth rate of the capital stock, output, or any other accounting aggregate,

or Henning Bohn (The Sustainability of Budget Deficits in a Stochastic Economy, JMCB 27(1), 1995),

discounting at the safe interest rate is usually incorrect. … popular fiscal policy “indicators” like deficit levels or debt-GNP ratios may provide very little information about sustainability. … the intertemporal budget constraint imposes very few restrictions on the average primary balance.

Recent work in which these themes appear include papers by Zhengyang Jiang, Hanno Lustig, Stijn Van Nieuwerburgh, and Mindy Xiaolan (Manufacturing Risk-free Government Debt, NBER wp 27786, 2020), Robert Barro (r Minus g, NBER wp 28002, 2020), or Stan Olijslagers, Nander de Vette, and Sweder van Wijnbergen (Debt Sustainability when r−g<0: No Free Lunch after All, CEPR dp 15478, 2020).

Intergenerational Risk Sharing

With overlapping generations the way the government manages its debt has implications for intergenerational risk sharing, see for example Henning Bohn (Risk Sharing in a Stochastic Overlapping Generations Economy, mimeo, 1998), Robert Shiller (Social Security and Institutions for Intergenerational, Intragenerational, and International Risk Sharing, Carnegie-Rochester Conference on Public Policy 50, 1999), or Gabrielle Demange (On Optimality of Intergenerational Risk Sharing, Economic Theory 20(1), 2002).

Long-Run Debt Dynamics and Fiscal Space

Dmitriy Sergeyev and Neil Mehrotra (Debt Sustainability in a Low Interest World, CEPR dp 15282, 2020) offer an analysis of long-run debt dynamics under the assumption that the primary surplus systematically, and strongly responds to the debt-to-GDP ratio such that the government’s intertemporal budget constraint is necessarily satisfied:

Population growth and productivity growth have opposing effects on the debt-to-GDP ratio due to their opposing effects on the real interest rate. Lower population growth leaves the borrowing rate unchanged while directly lowering output growth, shifting the average debt-to-GDP ratio higher. By contrast, when the elasticity of intertemporal substitution is less than one, a decline in productivity growth has a more than a one-for-one effect on the real interest rate, lowering the cost of servicing the debt and thereby reducing the average debt-to-GDP ratio. To the extent that higher uncertainty accounts for low real interest rates, we find that
the variance of the log debt-to-GDP ratio unambiguously increases with higher output
uncertainty. However, uncertainty also has an effect on the mean debt-to-GDP ratio that
depends on the coefficient of relative risk aversion. Higher uncertainty lowers the real
interest rate but this effect may be outweighed by an Ito’s lemma term due to Jensen’s
inequality that works in the opposite direction.

Sergeyev and Mehrotra also consider the effects of rare disasters as well as of a maximum primary surplus which implies that debt becomes defaultable and the interest rate on debt features an endogenous risk premium, generating the possibility of a “tipping point” with a slow moving debt crises as in Guido Lorenzoni and Ivan Werning (Slow Moving Debt Crises, AER 109(9), 2019).

Ricardo Reis (The Constraint on Public Debt when r<g But g<m, mimeo, 2020) analyzes a non-stochastic framework under the assumption that the marginal product of capital, m, exceeds the growth rate, g, which in turn exceeds the risk-free interest rate, r. Reis considers the case where m is the relevant discount rate, for example because r features a liquidity premium:

there is still a meaningful government budget constraint once future surpluses and debt are discounted by the marginal product of capital.

He shows the following:

  • The debt due to a one-time primary deficit can be rolled over indefinitely and disappears asymptotically as long as r<g.
  • With permanent primary deficits that grow at the same rate as debt and output, the government’s intertemporal budget constraint features a bubble component due to r<m. This corresponds to the usual seignorage revenue measure (see p. 173 in Niepelt, Macroeconomic Analysis, 2019).
  • Suppose that from tomorrow on, the primary deficit and debt quotas are given by d and b, respectively. Then, the present value of total net revenues in the government’s budget constraint equals [- d + (m – r)*b] / (m-g). Both m>g and g>r relax the constraint, as does a lower r.
  • Along a balanced growth path, b = [- d + (m – r)*b] / (m-g) and thus, d = (g-r)*b where d is assumed to be positive. Reis argues that b cannot be larger than total assets relative to GDP. Accordingly, the deficit cannot exceed total assets times (g-r).

Reis concludes that most of the bubble component “has already been used.” In addition to developing a model that yields m>g>r in equilibrium he also discusses the role of inflation (stable inflation generates fiscal space because it renders debt safer and thus increases demand for debt) and inequality (more inequality increases fiscal space).

Blanchard’s Presidential Address

In his presidential address, Olivier Blanchard (Public Debt and Low Interest Rates, AER 109(4), 2019) argues that the risk-free interest rate has fallen short of average US growth rate (and similarly, in other countries). Importantly—and implicitly addressing Abel, Mankiw, Summers, Zeckhauser, and Bohn (see above)—he also argues that risk is not that much of an issue as far as the sustainability of public debt is concerned:

Jensen’s inequality is thus not an issue here. In short, if we assume that the future will be like the past (admittedly a big if), debt rollovers appear feasible. While the debt ratio may increase for some time due to adverse shocks to growth or positive shocks to the interest rate, it will eventually decrease over time. In other words, higher debt may not imply a higher fiscal cost.

Most of his formal analysis doesn’t focus on debt though. Instead he analyzes the effects of risk-free social security transfers from young to old in a stochastic OLG economy. (There are close parallels between debt and such transfers to the old that are financed by contemporaneous taxes on the young.) In a steady-state with very low interest rates higher transfers have two effects on welfare, by (i) providing an attractive substitute for savings and by (ii) reducing capital accumulation and thereby lowering wages and raising the interest rate. If the economy initially is dynamically inefficient both effects are welfare improving because (i) capital accumulation with a low return is replaced by higher yielding intergenerational transfers and (ii) lower wages and higher interest rates are attractive, starting from a situation with a low interest rate. In a stochastic economy the first channel yields welfare gains as long as the growth rate exceeds the risk-free rate, and the second channel yields welfare gains (approximately) when the growth rate exceeds the marginal product of capital. Blanchard argues

[b]e this as it may, the analysis suggests that the welfare effects of a transfer may not necessarily be adverse, or, if adverse, may not be very large.

In the corresponding case with debt there is another effect because the intergenerational transfer is not risk-free; the size of this additional effect depends on the path of the risk-free interest rates (Blanchard assumes that the debt level is stabilized which requires net tax payments by the young to reflect the contemporaneous risk-free rate). In the slightly different case where debt is increased once and then rolled over, without adjusting taxes in the future, the sustainability and welfare implications are ambiguous and critically depend on the production function:

In the linear case, debt rollovers typically do not fail [my emphasis] and welfare is increased throughout. For the generation receiving the initial transfer associated with debt issuance, the effect is clearly positive and large. For later generations, while they are, at the margin, indifferent between holding safe debt or risky capital, the inframarginal gains (from a less risky portfolio) imply slightly larger utility. But the welfare gain is small … . In the Cobb-Douglas case however, this positive effect is more than offset by the price effect, and while welfare still goes up for the first generation (by 2 percent), it is typically negative thereafter. In the case of successful debt rollovers, the average adverse welfare cost decreases as debt decreases over time. In the case of unsuccessful rollovers, the adjustment implies a larger welfare loss when it happens. If we take the Cobb-Douglas example to be more representative, are these Ponzi gambles, as Ball, Elmendorf, and Mankiw (1998) have called them, worth it from a welfare viewpoint? This clearly depends on the relative weight the policymaker puts on the utility of different generations [my emphasis].

Blanchard argues that the marginal product of capital may be smaller than commonly assumed, implying that it is more likely that the welfare effects working through (ii) are positive (those working through (i) are very likely positive). Finally, he also presents some additional potential arguments pro and con higher public debt.

Blanchard’s work has attracted substantial criticism, for instance at the January 2020 ASSA meetings (see this previous post). In a short paper presented at the meetings, Johannes Brumm, Laurence Kotlikoff, and Felix Kubler (Leveraging Posterity’s Prosperity?) point out that a negative difference between average interest and growth rates is not necessarily indicative of dynamic inefficiency (see the discussion above) and that Blanchard’s analysis disregards tax distortions as well as the welfare effects from intergenerational risk sharing (again, see above):

To see the distinction between risk-sharing and a Ponzi scheme, modify B’s two-period model to include agents working when old if they don’t randomly become disabled. Now workers face second-period asset income and labor earnings risk. The government has no safe asset in which to invest. If it borrows, invests in capital, and taxes bond holders its excess return, “safe” debt is identical to risky capital. But if the net taxes are only levied on the non-disabled, bonds become a valued risk-mitigating asset and their return can be driven far below zero. This scheme could be, and to some extend it is, implemented through progressive taxation. If, observing this gap between growth and safe rates, the government decides to institute an “efficient” Ponzi scheme with a fixed pension benefit financed on a pay-go basis by taxes on workers, net wages when young will be more variable, raising generation-specific risk and potentially producing an outcome in which no generation is better off and at least one is worse off.

Brumm, Kotlikoff, and Kubler also note that the effective interest rate at which US households are borrowing is much higher than the borrowing rate of the government; this undermines Blanchard’s approach to gauge the welfare implications. And they point out that the scheme suggested by Blanchard could harm other countries by reducing global investment.

Jasmina Hasanhodzic (Simulating the Blanchard Conjecture in a Multi-Period Life-Cycle Model) simulates a richer OLG model and rejects the Blanchard conjecture of Pareto gains due to higher transfers:

It shows that the safe rate on government debt can, on average, be far less than the economy’s growth rate without its implying that ongoing redistribution from the young to the old is Pareto improving. Indeed, in a 10-period, OLG, CGE model, whose average safe rate averages negative 2 percent on an annual basis, welfare losses to future generations resulting from the introduction of pay-go Social Security, financed with a 15 percent payroll tax, are enormous—roughly 20 percent measured as a compensating variation relative to no policy.

Relative to Blanchard’s simulations, her model implies more negative consequences of crowding out on wages, a higher tax burden from the transfer scheme, and more induced old-age consumption risk.

Michael Boskin (How, When and Why Deficits Are Dangerous) offers a broad discussion of potential weaknesses of Blanchard’s analysis. Richard Evens (Public Debt, Interest Rates, and Negative Shocks) questions Blanchard’s simulations on calibration grounds and notes that he couldn’t replicate some of Blanchard’s findings.

On his blog, John Cochrane argues along similar lines as Ricardo Reis: Even if r<g, expected primary deficits are so large that debt quotas will explode nevertheless.

Olivier Blanchard on Markus’ Academy.

More work by Johannes Brumm, Xiangyu Feng, Laurence J. Kotlikoff, and Felix Kubler: When Interest Rates Go Low, Should Public Debt Go High? (NBER working paper 28951), and Deficit Follies (28952).

Note: This post was updated several times.

John Cochrane about CBDC and Me

Writing about CBDC, John Cochrane makes it clear that he is in favor. He links to my work and writes

Dirk Niepelt has written a lot about CBDC theory, including reserves for all in 2015, a recent Vox-EU summary and papers,  here with Markus Brunnermeier a JME paper “CBDC coupled with central bank pass-through funding need not imply a credit crunch nor undermine financial stability,” a follow up including “The model implies annual implicit subsidies to U.S. banks of up to 0.8 percent of GDP during the period 1999-2017.”  Here  “reserves for all” “does not affect macroeconomic outcomes,”