What is the term for a general increase in prices over time?

A general increase in prices over time is called inflation.

Inflation means that the overall price level for goods and services is rising, reducing the purchasing power of money. It does not require every individual price to increase: some items may become cheaper while the broad average rises. Economists track inflation with price indexes that combine many prices using defined weights.

In the United States, the Bureau of Labor Statistics’ Consumer Price Index measures price changes experienced by consumers. Other measures serve different purposes, including the Producer Price Index for prices earlier in the production process and the GDP price index for goods and services produced in the economy. Inflation is usually reported as a percentage change over a month or year.

Inflation is not the same as a single price spike. A one-time jump in gasoline prices can raise the price level, while sustained inflation describes continuing increases across the economy. Deflation is a general decline in prices; disinflation means inflation is slowing but prices are still rising. Stagflation combines weak economic performance with high inflation.