The Recession of 1920–1921 was a sharp deflationary economic contraction in the United States, United Kingdom and other countries, beginning 14 months after the end of World War I. It lasted from January 1920 to July 1921. The extent of the deflation was not only large, but large relative to the accompanying decline in real product. January 1920 – July 1921 · 1 year 6 months Business activity: −38.1% The 1921 recession began a mere 10 months after the post-World War I recession, as the economy continued working through the shift to a peacetime economy. The recession was short, but extremely painful. The year 1920 was the single most deflationary year in American history; production, however, did not fall as much as might be expected from the deflation. GNP may have declined between 2.5 and 7 percent, even as wholesale prices declined by 36.8%. The economy had a strong recovery following the recession. Dates: the National Bureau of Economic Research's business cycle chronology. Wiki link Wiki link