Price Realized Index Change Year-over-Year Calculator
Compute same-basket, adjacent-year index change; caller supplies matched periods and basket. Caller independently verifies observations, reference edition, units and applicability; not a grading-service certificate, authentication, conservation treatment, actual market price or legal/insurance entitlement.
Description
A price index can summarize relative change between two matched periods.
A price index can summarize relative change between two matched periods.1
This calculator reports the signed percentage change between supplied positive index values, without updating prices or adjusting individual items.
When to use Price Realized Index Change Year-over-Year Calculator
Use this tool when you need to summarize the supplied collecting records or matched observations. Prepare independently verified observations, reference edition/context, and matching units or currency basis.
How to use Price Realized Index Change Year-over-Year Calculator and understand its results
- Prepare independently verified observations, reference edition/context, and matching units or currency basis.
- Enter previousMatchedIndex, currentMatchedIndex, following the field table and calculation rules below, then run the tool.
- Read yearOverYearPercent. For result objects, inspect the nested output fields below, including any missing evidence or selected indices.
- Correct any input issues and run again. Before using a successful result, review its units, signs, evidence coverage, and stated model or reference assumptions.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| previousMatchedIndex | Previous matched index | number | Required |
| currentMatchedIndex | Current matched index | number | Required |
Require strictly positive prior and current finite indices under one reference basis. Divide current by prior, subtract one, and multiply by one hundred. The year-on-year label depends on independently chosen dates.
changePercent=100×(currentIndex/previousIndex−1) Read these symbols with the field meanings and branch or reference rules above.
| Output field | Meaning | Value type |
|---|---|---|
| yearOverYearPercent | Year over year percent | number |
{
"input": {
"previousMatchedIndex": 100,
"currentMatchedIndex": 110
},
"output": {
"yearOverYearPercent": 10.000000000000009
}
}Limitations and assumptions
Observations, reference edition, and applicability are independently supplied. Arithmetic and reference summaries do not provide authentication, a certified grade, or an actual market price.
Missing required fields, unknown fields, wrong types, and violated calculation rules return input issues. Numeric values must be finite; nonfinite numeric outputs are rejected.
Alternative or Complementary methods
For a related task, use Inflation Adjusted Historical Stamp Price Converter: Inflation adjustment compares a historic amount using two indices on the same basis. This converter applies a supplied index ratio and rounds to currency minor units without fetching an inflation series. For a complementary step, use Realized versus Estimate Hammer Variance Percent Calculator: A hammer-price variance compares an auction result with a stated estimate on the same currency basis. This calculator returns both the signed minor-unit difference and its percentage of the estimate.
References
Similar or alternative tools
- Inflation Adjusted Historical Stamp Price Converter
Inflation adjustment compares a historic amount using two indices on the same basis. This converter applies a supplied index ratio and rounds to currency minor units without fetching an inflation series.
- Realized versus Estimate Hammer Variance Percent Calculator
A hammer-price variance compares an auction result with a stated estimate on the same currency basis. This calculator returns both the signed minor-unit difference and its percentage of the estimate.