Archive · 4 Sep 2026
Economic Base-Year Revisions Mostly Preserve Growth Narratives
Economic statistics use a starting year called a base year for comparison.
Different measures currently use different base years, which can make comparisons harder.
New base years changed some past growth and inflation numbers.
GDP growth for FY24 was revised down significantly, but the overall direction of growth stayed similar.
Industrial production was different because the new data showed growth slowing in FY26.
Wholesale price inflation was also revised lower.
These changes did not provide enough new data to reconsider earlier interest-rate decisions.
The author says statistics should be updated more often so they better reflect the changing economy.
India now uses different base years for GDP, IIP, WPI, CPI, PPI and services indicators.
Revised GDP growth was 190 basis points lower for FY24 but 40-70 basis points higher in the following two years.
IIP revisions changed the narrative for FY26, showing a decline rather than unchanged growth.
WPI inflation was revised from 2.3% to 1.7% in FY25 and was 31 basis points lower in FY26.
The author recommends revising indicators about every five years and quickly updating major changes in economic composition.
- Who
- The author, the Chief Economist of Bank of Baroda, discusses revisions to India’s economic indicators.
- What
- The article examines whether changing base years and indicator compositions altered earlier economic narratives and policy assessments.
- When
- The comparisons cover FY24, FY25 and FY26; the article recommends revisions roughly every five years.
- Why
- To improve comparability, reduce distortions from outdated compositions and determine whether past data-based decisions should be reassessed.
Arguments for Alignment and Frequent Revisions
Evidence That Narratives Mostly Held
Using a common base year
Arguments for Alignment and Frequent Revisions
Aligning base years could improve comparability because indicators are used together, including in GDP deflators.
Evidence That Narratives Mostly Held
The article acknowledges the theoretical concern but finds that differing base years did not generally overturn the direction of the data.
Effect on policy interpretation
Arguments for Alignment and Frequent Revisions
Large revisions, particularly the 190-basis-point reduction in FY24 GDP growth, could have supported a different assessment of economic conditions.
Evidence That Narratives Mostly Held
The author says the change probably would not have mattered in the broader scheme of things, and there is not enough revised CPI data to retrospectively reassess repo-rate decisions.
How often to revise indicators
Arguments for Alignment and Frequent Revisions
The author favors more frequent revisions, suggesting an approximately five-year gap and immediate updates when economic composition changes substantially.
Evidence That Narratives Mostly Held
Longer gaps have been used previously—the last gap exceeded ten years and the preceding one was seven years—but the article argues these intervals are now too long for a rapidly changing economy.
- GDP base year
- 2022-23
- IIP and core-sector base year
- 2022-23
- WPI base year
- 2022-23
- CPI base year
- 2024, calendar year
- PPI base year
- 2022-23
- FY24 GDP revision
- New-series growth was 190 basis points lower than under the old series: 7.3% instead of 9.2%.
- FY25 WPI revision
- Inflation was revised from 2.3% to 1.7%.