📊 Purchasing Power Over Time
| Year | Equivalent Value | Cumulative Inflation | CPI |
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Understanding Inflation & Purchasing Power
Inflation is one of the most powerful forces shaping your financial life — yet most people underestimate its cumulative impact. Our calculator uses real US Bureau of Labor Statistics CPI data to show you exactly how purchasing power has changed across any time period since 1913.
What Is Inflation?
Inflation is the gradual increase in the price of goods and services over time. When inflation occurs, each dollar buys a smaller percentage of those goods. The US Federal Reserve targets about 2% annual inflation as healthy for economic growth.
Divide 70 by the inflation rate to estimate how many years it takes for prices to double. At 3.5% inflation, prices double in about 20 years. At 7%, they double in just 10 years.
How Inflation Affects Your Savings
If your savings earn 1% interest but inflation runs at 3%, your money loses 2% of its real purchasing power every year. After 20 years, $10,000 in a low-yield account could have the real-world spending power of under $7,000. This is why investing in assets that outpace inflation is essential for long-term wealth preservation.
Notable Inflation Periods in US History
- 1970s: ~7.4% average — oil shocks caused severe erosion of purchasing power
- 1980s: ~5.5% average — declining from peaks as Federal Reserve tightened policy
- 1990s: ~3.0% average — stable and moderate
- 2000–2019: ~2.1% average — historically low, near-target inflation
- 2021–2022: peaked at 9.1% — highest since 1981, driven by supply chain disruptions
Worried About Inflation Eroding Your Savings?
See how investing — rather than holding cash — can dramatically outpace inflation over time.
Try the Compound Interest Calculator →Frequently Asked Questions
What is inflation?
Inflation is the rate at which the general level of prices rises over time, reducing purchasing power. It's measured using the Consumer Price Index (CPI), which tracks price changes for a basket of common goods and services.
How does this calculator work?
This calculator uses real historical US CPI data from the Bureau of Labor Statistics. It calculates the exact ratio between the CPI in your start year and end year to determine how purchasing power has changed — no estimated rates needed.
What is a normal inflation rate?
The US Federal Reserve targets approximately 2% annual inflation as healthy. Sustained rates above 5% significantly erode purchasing power, while deflation can also harm the economy.
How does inflation affect my savings?
If your savings earn less than the inflation rate, you're losing real purchasing power. $10,000 in a 1% savings account during 4% inflation loses approximately $300 in real value annually.
What is the difference between CPI and inflation?
The Consumer Price Index (CPI) is the measurement tool — it tracks prices of a specific basket of goods. Inflation is the rate of change of the CPI over time. When people say "the inflation rate is 3%," they mean the CPI rose 3% compared to the previous year.