U.S. inflation rate in 1918: 17.97%

Inflation in 1918 and its effect on dollar value

Purchasing power decreased by 17.97% in 1918 compared to 1917. On average, you would have to spend 17.97% more money in 1918 than in 1917 for the same item.

In other words, $1 in 1917 is equivalent in purchasing power to about $1.18 in 1918.

The 1917 inflation rate was 17.43%. The inflation rate in 1918 was 17.97%. The 1918 inflation rate is higher compared to the average inflation rate of 2.83% per year between 1918 and 2020.

Inflation rate is calculated by change in the consumer price index (CPI). The CPI in 1918 was 15.10. It was 12.80 in the previous year, 1917. The difference in CPI between the years is used by the Bureau of Labor Statistics to officially determine inflation.

Inflation from 1917 to 1918
Average inflation rate 17.97%
Converted amount ($1 base) $1.18
Price difference ($1 base) $0.18
CPI in 1917 12.800
CPI in 1918 15.100
Inflation in 1917 17.43%
Inflation in 1918 17.97%

USD Inflation since 1913
Annual Rate, the Bureau of Labor Statistics CPI

Inflation by City

Inflation can vary widely by city, even within the United States. Here's how some cities fared in 1917 to 1918 (figures shown are purchasing power equivalents of $1):

Seattle, Washington experienced the highest rate of inflation during the 1 years between 1917 and 1918 (22.53%).

San Francisco, California experienced the lowest rate of inflation during the 1 years between 1917 and 1918 (16.53%).

Note that some locations showing 0% inflation may have not yet reported latest data.

Inflation by Country

Inflation can also vary widely by country. For comparison, in the UK £1.00 in 1917 would be equivalent to £1.22 in 1918, an absolute change of £0.22 and a cumulative change of 22.09%.

In Canada, CA$1.00 in 1917 would be equivalent to CA$1.13 in 1918, an absolute change of CA$0.13 and a cumulative change of 13.25%.

Compare these numbers to the US's overall absolute change of $0.18 and total percent change of 17.97%.

Inflation by Spending Category

CPI is the weighted combination of many categories of spending that are tracked by the government. Breaking down these categories helps explain the main drivers behind price changes. This chart shows the average rate of inflation for select CPI categories between 1917 and 1918.

Compare these values to the overall average of 17.97% per year:

Category Avg Inflation (%) Total Inflation (%) $1 in 1917 → 1918
Food and beverages 0.00 0.00 1.00
Housing 0.00 0.00 1.00
Apparel 39.39 39.39 1.39
Transportation 0.00 0.00 1.00
Medical care 0.00 0.00 1.00
Recreation 0.00 0.00 1.00
Education and communication 0.00 0.00 1.00
Other goods and services 0.00 0.00 1.00

For all these visualizations, it's important to note that not all categories may have been tracked since 1917. This table and charts use the earliest available data for each category.

How to Calculate Inflation Rate for $1, 1917 to 1918

Our calculations use the following inflation rate formula to calculate the change in value between 1917 and 1918:

CPI in 1918 CPI in 1917
1917 USD value
1918 USD value

Then plug in historical CPI values. The U.S. CPI was 12.8 in the year 1917 and 15.1 in 1918:


$1 in 1917 has the same "purchasing power" or "buying power" as $1.18 in 1918.

To get the total inflation rate for the 1 years between 1917 and 1918, we use the following formula:

CPI in 1918 - CPI in 1917CPI in 1917
Cumulative inflation rate (1 years)

Plugging in the values to this equation, we get:

15.1 - 12.812.8

Comparison to S&P 500 Index

To help put this inflation into perspective, if we had invested $1 in the S&P 500 index in 1917, our investment would be nominally worth approximately $0.96 in 1918. This is a return on investment of -3.81%, with an absolute return of $-0.04 on top of the original $1.

These numbers are not inflation adjusted, so they are considered nominal. In order to evaluate the real return on our investment, we must calculate the return with inflation taken into account.

The compounding effect of inflation would account for 15.23% of returns ($0.15) during this period. This means the inflation-adjusted real return of our $1 investment is $-0.18. You may also want to account for capital gains tax, which would take your real return down to around $0 for most people.

Investment in S&P 500 Index, 1917-1918
Original Amount Final Amount Change
Nominal $1 $0.96 -3.81%
Inflation Adjusted
$1 $0.82 -18.46%

Information displayed above may differ slightly from other S&P 500 calculators. Minor discrepancies can occur because we use the latest CPI data for inflation, annualized inflation numbers for previous years, and we compute S&P price and dividends from January of 1917 to latest available data for 1918 using average monthly close price.

For more details on the S&P 500 between 1917 and 1918, see the stock market returns calculator.

News headlines from 1917

Politics and news often influence economic performance. Here's what was happening at the time:

  • The Russian "February Revolution" begins alongside protests celebrating Women's Day and St Petersburg riots.
  • Tsar Nicholas II abdicates, nominating his brother, Grand Duke Michael, to succeed him.
  • President Wilson asks US Congress to declare war against Germany.
  • Vladimir Lenin issues the "April Theses" appealing for Soviets to take power during Russian Revolution.
  • Leon Trotsky becomes chairman of the Petrograd Soviet after the Bolsheviks gain control.

Data Source & Citation

Raw data for these calculations comes from the Bureau of Labor Statistics' (CPI), established in 1913. Inflation data from 1665 to 1912 is sourced from a historical study conducted by political science professor Robert Sahr at Oregon State University.

You may use the following MLA citation for this page: “Inflation Rate in 1918 | Inflation Calculator.” Official Inflation Data, Alioth Finance, 29 Oct. 2020, https://www.officialdata.org/inflation-rate-in-1918.

Special thanks to QuickChart for their chart image API, which is used for chart downloads.

in2013dollars.com is a reference website maintained by the Official Data Foundation.

Ian Webster

About the author

Ian Webster is an engineer and data expert based in San Mateo, California. He has worked for Google, NASA, and consulted for governments around the world on data pipelines and data analysis. Disappointed by the lack of clear resources on the impacts of inflation on economic indicators, Ian believes this website serves as a valuable public tool. Ian earned his degree in Computer Science from Dartmouth College.

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» Read more about inflation and investment.

Inflation from 1917 to 1918
Average inflation rate 17.97%
Converted amount ($1 base) $1.18
Price difference ($1 base) $0.18
CPI in 1917 12.800
CPI in 1918 15.100
Inflation in 1917 17.43%
Inflation in 1918 17.97%