On his blog, JP Koning offers two explanations for the surprisingly high rupee notes redemption rate—nearly 99%—after last year’s demonetization experiment: Money laundering, and a partial amnesty.

Indians who had large quantities of illicit cash were able to contract with those who had room below their ceiling to convert illicit rupees on their behalf …

Two weeks after the initial … announcement, the government introduced a formal amnesty for demonetized banknote holders. Any deposit of cash above the ceiling would only be taxed at 50%, assuming it was declared. If not declared, the funds might still get through the note blockade undetected, although if apprehended an 85% penalty was to be levied. These new options were better than throwing away one’s stash altogether and suffering a sure 100% loss …

As a consequence, the windfall for the government likely was smaller than expected. But poorer Indians may still have benefited, by selling their services in the money laundering scheme.