The Economist recounts the reasons why the quality of GDP measurement is lacking and why GDP measures cannot answer all the questions they are used to address.
Like Mr Piketty, he begins with piles of data assembled over years of research. He sets the trends of different individual countries in a global context. Over the past 30 years the incomes of workers in the middle of the global income distribution—factory workers in China, say—have soared, as has pay for the richest 1% (see chart). At the same time, incomes of the working class in advanced economies have stagnated. This dynamic helped create a global middle class. It also caused global economic inequality to plateau, and perhaps even decline, for the first time since industrialisation began. …
Mr Milanovic suggests that both [Kuznets and Piketty] are mistaken. Across history, he reckons, inequality has tended to flow in cycles: Kuznets waves.
In the FT, Martin Wolf argues that a significant part of the (British) welfare state is about insurance rather than redistribution:
Evidence for this comes from another IFS study … This examined the effects of the tax and benefit systems on people born between 1945 and 1954 …
First, income is far less unequal over lifetimes than in any given year. This is because a big proportion of inequality is temporary … Second, largely as a result, more than half of the redistribution achieved by taxes and benefits is over lifetimes rather than among different people. Third, in the course of adult life, only 7 per cent of individuals receive more in benefits than they pay in taxes, even though 36 per cent of people receive more in benefits than they pay in taxes in any given year. Finally, in-work benefits are just as good as out-of-work benefits at helping people who remain poor throughout their lives but they do less damage to incentives to work. Higher rates of income tax, meanwhile, target the “lifetime rich” relatively well because mobility at the top is relatively modest.
Marcel Fratzscher also wrote a book on the topic, focusing on Germany. He argues that the “Verteilungskampf” (redistributive struggle) intensifies and that equality of opportunity is being lost. In the FAZ, Jan Hauser summarizes a critique of the book by another Berlin based professor, Klaus Schroeder, who argues that the text is very short on substance.