Rebasing
Changing an index's base period. It moves the index level but not inflation rates.
2 min read · Reviewed September 2026
In plain words
Rebasing divides every index value by the value in the new base year, setting that year to 100. It changes the absolute level of the index but leaves all inflation rates unchanged — rebasing is cosmetic, not substantive.
Frequently asked questions
Does rebasing affect inflation rates?
No. Rebasing is purely cosmetic — it changes the level of the index numbers but not the percentage changes between any two periods. Inflation rates are ratios, so they are unaffected by which base year you choose.
Further reading