CPI is central to India's inflation-targeting monetary policy framework. Analyse how outdated base years can distort policy outcomes.

Under the Flexible Inflation Targeting framework, the RBI's Monetary Policy Committee is mandated to hold headline CPI inflation at 4% (±2%). Since MoSPI compiles the index and the RBI only targets it, the credibility of policy rests on how faithfully the CPI basket mirrors actual household consumption — a fidelity that decays as the base year ages.

CPI as the anchor of the framework

• CPI is the single target variable for the MPC; repo rate decisions, liquidity operations and inflation expectations management all key off it.
• It is also the deflator for real interest rates, and the escalator for DA, wage indexation and welfare transfers — so index error propagates well beyond monetary policy.

How an outdated base distorts outcomes

• Stale weights: the 2012=100 series drew weights from 2011-12 consumption. Over a decade of urbanisation, rising incomes and services growth left food over-weighted and services under-weighted [1].
• Measurement bias in the target: over-weighted food transmits volatile supply shocks into headline inflation, pushing the MPC toward rate action against price movements monetary policy cannot correct.
• Missing consumption: the old basket omitted digital and e-commerce spending; the revised series expands the weighted basket from 299 to 358 items (services 40→50) [1].
• Narrow price capture: prices drawn only from physical markets ignore online price formation, understating a fast-growing channel [2].
• Cumulative policy cost: a biased index means real rates, welfare indexation and fiscal projections are all mis-set — errors compound across the economy.

Corrective direction

• New base 2024=100, released 12 February 2026, with weights from HCES 2023-24 and COICOP 2018 classification for global comparability [1].
• Coverage widened to 1,465 rural and 1,395 urban markets across 434 towns, plus 12 online markets in towns above 25 lakh population [2].

An inflation target is only as sound as the index measuring it. The 2024 revision restores that measurement base; institutionalising shorter, rule-bound revision cycles — as recommended by the Expert Group on CPI updation [3] — would ensure the MPC always acts on prices households actually pay.