In 1934, Currie constructed the first money supply and income velocity series for the United States. He blamed the government's "commercial loan theory" of banking for monetary tightening in mid-1929, when the economy was already declining, and then for its passivity during the next four years in the face of mass liquidations and bank failures. Instead, he advocated control of the money supply to stabilize income and expenditures. Currie cited his colleague and Soviet agent Silverman for his "many helpful suggestions and criticisms" in the formation of this line of thinking.