$100 in 1978 has the buying power of $516.78 in September 2026. Prices are 416.8% higher, an average of 3.47% a year, by the official Consumer Price Index (CPI-U): 1978's average index was 65.2 and September 2026's is 336.940. Put the other way, $100 in September 2026 buys what $19.35 did in 1978.
Inflation in 1978 was 7.6% (the change in the year's average CPI from 1977; December to December, 9.0%), the 17th highest of the 112 years since 1914.
| Year | Average CPI-U | Inflation | $100 then is worth today |
|---|---|---|---|
| 1973 | 44.4 | +6.2% | $758.87 |
| 1974 | 49.3 | +11.0% | $683.45 |
| 1975 | 53.8 | +9.1% | $626.28 |
| 1976 | 56.9 | +5.8% | $592.16 |
| 1977 | 60.6 | +6.5% | $556.01 |
| 1978 | 65.2 | +7.6% | $516.78 |
| 1979 | 72.6 | +11.3% | $464.10 |
| 1980 | 82.4 | +13.5% | $408.91 |
| 1981 | 90.9 | +10.3% | $370.67 |
| 1982 | 96.5 | +6.2% | $349.16 |
| 1983 | 99.6 | +3.2% | $338.29 |
3.47% a year, compounded from the middle of 1978 to September 2026: prices are 416.8% higher in all, so a dollar from 1978 is worth $5.17 today.
The Bureau of Labor Statistics' Consumer Price Index for All Urban Consumers (CPI-U), all items, U.S. city average, not seasonally adjusted, which runs back to January 1913. A year's figure is the average of its monthly indexes, as BLS computes annual averages; today's figure is the latest month, September 2026, so the answer moves each month when BLS publishes a new CPI.
1977 · Inflation calculator, any month since 1913 · 1979
Source: BLS CPI-U, all items, U.S. city average, not seasonally adjusted (FRED CPIAUCNS); through 2006, BLS's official annual averages. The answer moves each month, when BLS publishes a new CPI.