At the close of 2018, the U.S. national debt was 107.2% of the nation's economy. Over the course of U.S. history, the national debt has averaged 29.9% of the economy. Thus, the current national debt is 258%, or 3.6 times, higher than its average over U.S. history. Economists frequently measure the government debt of nations relative to the size of their economies because this accounts for population growth, some of the effects of inflation, and the relative capacity of government to service its debt.