Value of $100 in 1918, adjusted to 1940

What happened to prices between 1918 and 1940

Between 1918 and 1940, the Consumer Price Index went from 15.1 to 14. Cumulatively, prices declined 7.3%, which works out to an average of -0.34% per year. Put differently, a dollar in 1918 bought what $1.08 buys in 1940.

1918 brought the steepest annual price increase the CPI had recorded: consumer prices rose 18.0% for the year, edging out 1917’s already sharp 17.4% as the economy stayed at full wartime mobilization for most of the year. A first-class stamp cost 3 cents, up from 2 cents the previous November under the War Revenue Act’s wartime tax increases. The war itself ended on November 11, when Germany signed an armistice with the Allied powers after more than four years of fighting in Europe, but the inflation built up over a year and a half of mobilization did not disappear along with the fighting. The bigger public health story that year was the influenza pandemic that reached the U.S. in a mild spring wave and then returned that fall in a far deadlier form, eventually killing roughly 675,000 Americans, more than the country’s combat losses in the war. It hit factories, docks, and shops alongside households, adding disruption to an economy already strained by wartime demand. Prices would keep climbing even after the armistice, into the postwar surge of 1919.

More about inflation in 1918 →

The destination year: 1940

Consumer prices rose 0.7% in 1940, snapping 1939’s decline and marking the first increase since 1937. The gain was modest, and the CPI still stood 18.1% below its 1929 peak, a reminder of how far the recovery from the Depression’s trough had left to go even as defense orders from Britain and France began reaching American factories. War was already reshaping domestic policy well before it touched American soil. Congress passed the Selective Training and Service Act that September, the country’s first peacetime draft, requiring men aged 21 to 35 to register and authorizing the induction of up to 900,000 men a year, more than a year before Pearl Harbor. That November, Franklin Roosevelt won an unprecedented third term, defeating Republican Wendell Willkie after campaigning on keeping the United States out of the war then consuming Europe and Asia. The promise would not hold much longer: within two years, wartime demand would push consumer prices up faster than at any point since the aftermath of World War I. First-class postage held at 3 cents, and the federal minimum wage stayed at 30 cents an hour, the level set the previous October under the Fair Labor Standards Act.

More about inflation in 1940 →