Chart of Consumer Price Index, 1800-2005
The Consumer price index shows the average change of prices over time in a market basket of goods and services. This measures the rate of inflation. Note: An estimate for 2005 is based on the change in the CPI from first quarter 2004 to first quarter 2005.

Notice how the peaks in inflation over the last 200 years have coincided with major wars.

Also note that the USA went off the gold standard in 1933.