Deflation

A condition of decreasing prices. Deflation is generally measured by the Consumer Price Index.

Deflation, the opposite of inflation, is a gradual drop in the cost of goods and services, usually caused by a surplus of goods and a shortage of cash.

Although deflation seems to increase your buying power in its early stages, it is generally considered a negative economic trend. That's because it is typically accompanied by rising unemployment, falling production, and limited investment.