India has initiated a comprehensive revision of the base year for Gross Domestic Product (GDP), Consumer Price Index (CPI) and Index of Industrial Production (IIP). The exercise is aimed at improving the relevance, accuracy and international comparability of key macroeconomic indicators. Base year revision is a standard statistical process used to reflect structural changes in the economy and to update weights, methods and data sources.
Why Base Year Revision Matters
The base year is the reference year against which economic activity is measured. Over time, consumption patterns, industrial composition and production structures change. A revised base year helps capture these changes more accurately. It also improves the quality of estimates used for policy-making, inflation tracking and industrial analysis.
Role of Technical Advisory Committees
The revision work is being guided by respective Technical Advisory Committees. These committees include experts from academia, the Central and State governments, and the Reserve Bank of India. Their role is to examine methodology, suggest improvements and ensure that the revised series reflects current economic realities. The exercise includes:
- Methodological improvements.
- Incorporation of new data sources.
- Updating of weights and item baskets.
- Alignment with current statistical standards.
Timelines for New Series
The new series of GDP is scheduled for release on 27 February 2026. The new CPI series is expected on 12 February 2026. The revised IIP series is planned for May 2026. These updates are because GDP and CPI are among the most closely watched indicators of economic performance and inflation trends.
SDDS and Data Standards
CPI and GDP are aligned with the IMF’s Special Data Dissemination Standard (SDDS). SDDS has four main aspects – coverage, periodicity and timeliness, public access, integrity, and quality of disseminated data. Compliance with such standards strengthens transparency and supports international comparability of official statistics.
Last Modified: April 28, 2026