Choose a solve mode for past value, current-equivalent amount, or implied past year. Enter the reference year and an assumed constant annual inflation or deflation rate; the editable 3% default is illustrative and does not use historical CPI data. An implied year can be fractional.
Past Value Formula
The following equation is used to calculate the Past Value.
- Where PV is the past value ($)
- CA is the current amount ($)
- i is the annual inflation (or deflation) rate
- n is the number of years into the past
To calculate the past value, divide the current amount by (1 + i) raised to the nth power.
What is a Past Value?
Definition:
Past value refers to the estimated worth or purchasing power of a current amount of money at a specific point in the past, factoring in rates of inflation or deflation.
How to Calculate Past Value?
Example Problem:
The following example outlines the steps and information needed to calculate the Past Value.
First, determine the current amount. In this example, we will use $1,000.
Next, determine the annual inflation rate and the number of years in the past. Assume the rate is 3% per year, and the target date is 5 years in the past.
Finally, calculate the past value using the formula above:
PV = $1,000 / (1 + 0.03)^5
PV ≈ $862.61
FAQ
What factors can affect the past value calculation?
This calculator applies one assumed annual rate throughout the entered interval. Its accuracy depends on whether that assumption represents the currency, region and period; it does not retrieve historical inflation or deflation data.
Why might different inflation indices yield different past values?
Various organizations calculate inflation using different methodologies and market baskets, potentially leading to slight variations in inflation rates. Different indices can produce different purchasing-power estimates. This calculator uses an entered constant rate rather than an index series.
Can I use this calculator to compare past values for different regions or currencies?
For comparison across different regions or currencies, you would need region-specific inflation data or exchange rates. Using a single country’s inflation rate for a different country’s currency could lead to inaccurate comparative results.
