MPPSC 2026 Prelims Paper-I · Question 49 of 100

Correct — D, 2024. The National Statistical Office, under the Ministry of Statistics and Programme Implementation (MoSPI), shifted the Consumer Price Index to a new base of 2024 = 100, replacing the 2012 = 100 series. The revised series was launched with the January 2026 CPI release in February 2026. Its weights are drawn from the Household Consumption Expenditure Survey (HCES) 2023-24 using the Modified Mixed Reference Period, and the basket is reclassified on COICOP 2018. Because households now spend a smaller share of their budget on food, the weight of 'food and beverages' falls from about 45.9 per cent in the old series to about 36.8 per cent in the new one, while the item basket widens from 299 to 358 items.

• (a)2011 — Not a CPI base year. The number is familiar because '2011-12' is the base of the GDP series and the reference year of the consumer expenditure survey that supplied the weights for the outgoing CPI — but the index base itself was 2012, not 2011.
• (b)2012 — This is the OLD base year (2012 = 100) that has just been replaced. It is the most tempting option because it was the correct answer for over a decade — the question is precisely about the change away from it.
• (c)2023 — Confuses the survey with the index. The Household Consumption Expenditure Survey used for the new weights ran in 2023-24, but the base year of the index itself is 2024.

A price index measures today's prices against a reference year whose level is set at 100 — that reference year is the base year. The base has to be revised periodically because both the basket of goods and services people buy and the share of spending on each item drift over time; an index anchored to a stale basket steadily misstates the cost of living. India revises the CPI base using fresh household consumption survey data, which is why the 2024 = 100 series takes its weights from HCES 2023-24. The CPI (Combined) is the number that matters for policy: the RBI's flexible inflation-targeting framework is defined on it, with a 4 per cent target and a tolerance band of plus or minus 2 percentage points.

Base-year questions are pure discrimination tests — the setter puts the outgoing base (2012) and the survey year (2023) next to the answer and waits. Fix three separate dates in your head and never let them merge: the base year of the index (2024), the year of the survey that produced the weights (2023-24) and the month of first release under the new base (January 2026 data, published February 2026). The same trap runs in WPI questions, where the base year and the effective date of the new series are different things.

• New CPI base: 2024 = 100, replacing 2012 = 100; compiled by the NSO under MoSPI
• Weights derived from the Household Consumption Expenditure Survey 2023-24 (Modified Mixed Reference Period); classification updated to COICOP 2018
• Weight of food and beverages falls from about 45.9 per cent to about 36.5 per cent (34.77 food + 1.77 beverages); item basket widens from 299 to 358 items
• The revised series was first released with the January 2026 CPI, published in February 2026
• The RBI's flexible inflation-targeting framework uses CPI (Combined) — 4 per cent target with a plus/minus 2 percentage point band

• Marking 2012 out of habit — it was the right answer for the previous decade
• Confusing the survey year (2023-24) with the index base year (2024)
• Believing the RBI targets WPI — it targets CPI (Combined)
• Assuming all Indian price indices share one base year; WPI, CPI and the IIP each have their own

State PSCs ask the base year as bare one-line recall, usually within a year or two of a revision; UPSC asks the same material as multi-statement questions on which index covers services, which has the higher food weight, and which one the RBI actually targets.

• practice — not a real PYQ

  The Consumer Price Index (Combined), used by the Reserve Bank of India for inflation targeting, is compiled and released by:

  • (a)The Reserve Bank of India
  • (b)The Labour Bureau
  • (c)The National Statistical Office under MoSPI
  • (d)The Department for Promotion of Industry and Internal Trade

  Answer(c) The National Statistical Office under the Ministry of Statistics and Programme Implementation.

• practice — not a real PYQ

  The base year of a price index is revised periodically mainly in order to:

  • (a)Lower the measured rate of inflation
  • (b)Align the basket and the item weights with current consumption patterns
  • (c)Comply with a statutory requirement to revise it every year
  • (d)Allow the index to be compared with foreign currencies

  Answer(b) Align the basket and the item weights with current consumption patterns, so the index keeps measuring the actual cost of living.