Calculate Annual CPI Increase
This example calculates the Canadian All-Items CPI increase for September 2026.
CPI Increase compares the CPI for a selected month with the CPI for the same month one year earlier.
Example
We want to calculate:
| Input | Value |
|---|---|
| Country | Canada |
| CPI Series | All-Items |
| Ending year | 2026 |
| Month | September |
The comparison is:
September 2026
compared with
September 2025
CPI values
For this example:
September 2026 CPI 170.0
September 2025 CPI 164.9
The calculation is:
(170.0 / 164.9) - 1
which produces a CPI Increase of:
3.1%
Method 1: Review CPI Increase in the task pane
The CPI Data section displays CPI Increase for the latest observation in the selected series.
To view the latest CPI Increase:
- Select Canada.
- Select All-Items.
- Select Load CPI Data.
- Review CPI Increase in the series preview.
For September 2026, the preview displays:
CPI Increase 3.1%
Method 2: Use FINPACK.CPIINCREASE
To calculate the same result directly in an Excel cell, enter:
=FINPACK.CPIINCREASE("ca","all-items",2026,9)
The function returns the numeric ratio:
0.031
Format the Excel cell as a percentage with one decimal place to display:
3.1%
Use cell references
Suppose the worksheet contains:
| Cell | Value |
|---|---|
| A2 | ca |
| B2 | all-items |
| C2 | 2026 |
| D2 | 9 |
Enter:
=FINPACK.CPIINCREASE(A2,B2,C2,D2)
The formula now uses the country, series, year, and month stored in those cells.
This makes it easy to build a worksheet where the CPI comparison changes when the input cells change.
Why the same month matters
CPI Increase is a same-month year-over-year comparison.
For example:
September 2025 to September 2026
represents a 12-month comparison.
The comparison is not based on the average CPI during the year.
For comparisons between average CPI periods, use FINPACK.CPIAVGCHANGE.
Estimated observations
If either CPI observation used in the comparison is estimated, the task pane identifies the CPI information accordingly.
The worksheet function continues to return a numeric result so that it can be used in other Excel calculations.
When estimated-data status is important, review the corresponding CPI information in the finPack task pane or inserted CPI history.
Related topics
FINPACK.CPI— Retrieve the individual CPI values used in a comparison.FINPACK.CPIINCREASE— Complete function reference.FINPACK.CPIAVGCHANGE— Complete function reference.- CPI Value — Detailed instructions for the task-pane feature.
- Calculate Annual CPI Increase — Compare the selected month with the same month one year earlier.
- Estimated CPI Observations — How finPack identifies estimated CPI data.
- CPI Data — Review the latest CPI Increase in the task pane.
- Compare Average CPI Periods — Compare consecutive average CPI periods instead of individual monthly observations.