What Happened
- MoSPI released India's first retail inflation data under the new CPI series (Base Year: 2024=100) on February 12, 2026; the January 2026 inflation reading under the new series was 2.75%.
- The old CPI series (Base Year: 2012=100) was simultaneously discontinued for the headline inflation figure, though a back series was released to provide historical comparability.
- The key structural change is a significant reduction in the weight of food and beverages from 45.86% to 36.75%, reflecting updated household expenditure patterns from the Household Consumption Expenditure Survey (HCES) 2023-24.
- Despite the new basket, the broad inflation narrative remained similar — the change in base year did not dramatically alter the trend, though the January 2026 reading was notably lower under the new series compared to what the old series might have shown.
- MoSPI also released companion FAQs explaining that the new series uses COICOP 2018 classification and covers 358 commodities across 12 divisions.
Static Topic Bridges
Why Base Year Revisions Matter: The Laspeyres Index Problem
India's CPI is a Laspeyres-type price index — it measures how much a fixed basket of goods and services (defined in the base year) would cost in the current period, relative to the base period. This methodology means that as consumption patterns change over time (people shifting from cereals to services, from kerosene to LPG), the fixed basket becomes increasingly unrepresentative. Periodic base year revisions update the basket and weights to reflect current spending patterns, ensuring the index remains a valid measure of the cost of living.
- Index type: Modified Laspeyres (fixed base period quantities, but updated periodically)
- Base year philosophy: A "normal" year — no major disruptions, comprehensive survey data available
- HCES 2023-24: The first comprehensive Household Consumption Expenditure Survey since NSSO 2011-12 (a gap of 12 years, as the planned 2017-18 survey was suppressed)
- Previous base revisions: 1982 → 2010 (for specific sub-indices); 2010 → 2012 (combined CPI adopted in 2015)
- New base: 2012 → 2024 (adopted February 2026)
- Base period prices collected: January–December 2024
Connection to this news: The 12-year lag between the 2011-12 HCES and the 2023-24 HCES means the 2012-base CPI was using badly outdated weights for the last decade. The new weights substantially reduce food's share (from 45.86% to 36.75%), reflecting India's structural shift toward services consumption.
Structural Shift in India's Consumption Basket
The HCES 2023-24 — the first household consumption survey in 12 years — revealed a significant structural shift in Indian household expenditure. Food's share in total consumption expenditure has fallen as incomes have risen, while spending on health, education, transport, and communication has increased. This "Engel's Law" pattern — where the share of income spent on food falls as income rises — is now embedded in the new CPI weights. The implication is that future food price shocks will have a smaller mechanical impact on headline CPI than under the old series.
- Engel's Law: As income rises, food's share in consumption falls — a universal empirical regularity
- HCES 2023-24: Published by MoSPI; it also fed into the new GDP series (private consumption estimates) and updated poverty estimates
- Food and beverages weight change: 45.86% (2012 series) → 36.75% (2024 series) — a reduction of ~9 percentage points
- New categories gaining weight: Health, education, recreation, communication — reflecting services economy growth
- Implications: CPI will now be less sensitive to food inflation spikes, which were a key driver of past inflation breaches of the 6% upper tolerance band
Connection to this news: The "same inflation story" headline in the article reflects the observation that while weights shifted significantly, the January 2026 CPI reading (2.75%) was not radically different from what the old series might have shown — suggesting both series broadly capture the same underlying price dynamics, even as the structural weights differ.
CPI as the Monetary Policy Anchor: Continuity and the Back Series
When the CPI base year changes, there is a practical concern for monetary policy: the MPC has been operating under the old series and needs to assess whether the new series produces structurally different inflation readings. MoSPI addresses this by releasing a "back series" — recalculated historical inflation figures under the new base year methodology. The back series allows the MPC to assess whether the new series is broadly continuous with the old, or if it introduces a systematic upward or downward shift.
- Back series: MoSPI releases historical CPI data recalculated under new methodology for continuity assessment
- RBI policy anchor: CPI (combined), compiled by MoSPI — used under Section 45ZA of the RBI Act
- Inflation target: 4% ± 2% (band: 2-6%) — the target applies regardless of base year
- January 2026 reading: 2.75% CPI (new series, base 2024=100) — well within the 2-6% target band
- If the new series systematically shows lower inflation (due to reduced food weight), it could allow RBI more room for rate cuts — a policy-relevant implication
- MoSPI simultaneously revised base years for GDP (2022-23) and IIP (2022-23) alongside CPI (2024)
Connection to this news: The release of the back series alongside the new index is crucial for monetary policy credibility — it allows the MPC to judge whether the low January 2026 reading (2.75%) reflects genuine disinflation or an artefact of the new methodology.
Key Facts & Data
- New CPI base year: 2024=100 (first data: February 12, 2026; covers January 2026)
- Previous base year: 2012=100
- January 2026 CPI (new series): 2.75%
- Food and beverages weight: 45.86% (2012) → 36.75% (2024) — reduction of ~9 percentage points
- Weights source: Household Consumption Expenditure Survey (HCES) 2023-24
- Classification: COICOP 2018 (12 divisions, 43 groups, 92 classes, 162 subclasses, 358 items)
- Base period prices: Collected January–December 2024
- Back series released: Yes — for historical comparability
- Compiled by: NSO, MoSPI; released monthly (provisional data ~2 weeks after reference month)
- RBI target: 4% CPI ± 2% (Section 45ZA, RBI Act, as amended by Finance Act 2016)
- HCES 2023-24: First comprehensive household survey since 2011-12 (12-year gap)