Finance Formula • Published on September 01, 2026 • Last updated September 01, 2026
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Consumer Price Index in current target period
Consumer Price Index in previous reference period
The Inflation Rate Formula calculates the percentage change in the Consumer Price Index (CPI) over a specific period, measuring price inflation and purchasing power loss.
CPI is a price level index relative to a base year, while Inflation Rate is the percentage growth rate of CPI.
A negative inflation rate represents deflation, where average prices fall over time.
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