When did prices double after 1978?
By August 1990, prices were twice their 1978 average (CPI-U 65.2 → 130.5), 12 years later. They had tripled by August 2005.
What $1 from 1978 is worth today
$1 in 1978 = $5.17 in September 2026
$1 from 1978$5.17in September 2026 dollars
Prices since 1978+417%CPI 65.2 → 336.9
Average a year3.46%compounded since 1978
Inflation in 19789.0%December to December
Worth in September 2026$516.52
Prices changed416.5%
Average a year3.46%
$100.00 in 1978 buys what $516.52 buys in September 2026.$100.00 × CPI 336.940 ÷ CPI 65.233 · a whole year uses its average CPI
BLS CPI-U, U.S. city average, not seasonally adjusted, through September 2026 (3.7% over 12 months). Source
1978 dollars in September 2026 dollars
| In 1978 | In September 2026 |
|---|---|
| $1.00 | $5.17 |
| $5.00 | $25.83 |
| $10.00 | $51.65 |
| $20.00 | $103.30 |
| $50.00 | $258.26 |
| $100.00 | $516.52 |
| $500.00 | $2,583 |
| $1,000 | $5,165 |
| $10,000 | $51,652 |
| $50,000 | $258,258 |
| $100,000 | $516,515 |
$100 from 1978, decade by decade
| Year | Worth | Average CPI |
|---|---|---|
| 1988 | $181.29 | 118.3 |
| 1998 | $249.89 | 163.0 |
| 2008 | $330.05 | 215.3 |
| 2018 | $384.94 | 251.1 |
| September 2026 | $516.52 | 336.9 |
1978 in the inflation record
- Prices rose 9.0% in 1978 (December to December), above the 3.3% average of every year since 1914: #11 of 112 from highest to lowest.
- The 1970s averaged 7.4% a year; the decade’s highest was 1979 at 13.3%.
- Prices first stood at twice their 1978 level in August 1990, and three times in August 2005.
- A dollar today buys what 19.4¢ bought in 1978.
CPI-U each month of 1978
| Month | CPI-U |
|---|---|
| January | 62.500 |
| February | 62.900 |
| March | 63.400 |
| April | 63.900 |
| May | 64.500 |
| June | 65.200 |
| July | 65.700 |
| August | 66.000 |
| September | 66.500 |
| October | 67.100 |
| November | 67.400 |
| December | 67.700 |
| Year average | 65.233 |
U.S. Bureau of Labor Statistics, CPI-U, U.S. city average, all items, not seasonally adjusted (1982-84 = 100). Source
Frequently asked questions
How much is $1 from 1978 worth today?
$5.17 in September 2026. Prices have risen 416.5% since 1978, using the 1978 average CPI-U of 65.233 and the September 2026 CPI-U of 336.940 from the U.S. Bureau of Labor Statistics.
What was the inflation rate in 1978?
Prices rose 9.0% from December 1977 to December 1978 (CPI-U, not seasonally adjusted).
What is the average inflation rate since 1978?
3.46% a year, compounded, from 1978 to September 2026. At that rate prices double about every 20 years.
How much is $100 from 1978 worth today?
$516.52. Multiply any 1978 amount by 5.165 to get today’s money.