In 1920, Charles Ponzi promised clients a 50% profit within 45 days or 100% profit within 90 days, by buying discounted postal reply coupons in other countries and redeeming them at face value in the U.S. as a form of arbitrage. In reality, Ponzi was paying earlier investors using the investments of later investors. His scheme ran for over a year before it collapsed, costing his “investors” $20 million (or $207 million in 2022 dollars)
