Between 1800 and 1916, total government expenditures in the United States generally ranged between 2% and 3% of GDP. There were higher peaks for the War of 1812 (5.1%) and the Civil War (13.8%), but in both cases pre-war government spending levels were re-established within about a decade after the end of the conflict. Even after WWI, the wartime peak of government spending (24.2% of GDP) declined rapidly to a slightly higher than historical spending base (3%) by the mid-1920s.
