Friedman concentrated on the failures before 1933 and points out that between 1929 and 1932 the Federal Reserve allowed the money supply to fall by a third which is seen as the major cause that turned a normal recession into a Great Depression.
傅利曼專注於1933年以前的錯誤，他指出1929年至32年間，聯邦準備系統允許貨幣供給下降了三分之一，這看來是造成正常衰退變成大蕭條的主因。