Distinguish between WPI and CPI as measures of inflation in India. Discuss the significance of the recent revision of WPI's base year to 2022-23.

India measures inflation through two parallel yardsticks — the Wholesale Price Index (WPI), compiled by the Office of the Economic Adviser, DPIIT, and the Consumer Price Index (CPI), compiled by MoSPI [1][3]. The revision of WPI's base year from 2011-12 to 2022-23, effective from the release dated 15 June 2026, is the most significant methodological update to the series in over a decade [1].

WPI and CPI distinguished

• Stage of transaction: WPI captures price change at the wholesale/first bulk transaction level; CPI captures retail prices actually paid by households [1][3].
• Coverage: WPI's headline basket covers only goods; CPI covers goods and services such as health, education and transport. Services enter the producer-price framework only through the separate Service PPI (seven services, including banking, insurance, railways and telecom) [2].
• Compiling authority: WPI — DPIIT, Ministry of Commerce & Industry; CPI — MoSPI/NSO [1][3]. This is a frequently confused distinction.
• Policy use: CPI (Combined) is the RBI's anchor for flexible inflation targeting at 4% ± 2%; WPI serves mainly as a leading indicator of cost-push pressure and a deflator in national accounts [4]. Thus in August 2026, WPI fuel and power inflation of 22.93% signalled upstream cost pressure ahead of retail pass-through [3].

Significance of the 2022-23 revision

• Representativeness: the item basket expanded from 697 to 957 items, with solar, wind and nuclear electricity brought under the 'Electricity' group — reflecting the post-pandemic, energy-transitioning economy [1].
• Global comparability: it aligns WPI's methodology with international Producer Price Index (PPI) standards, launched alongside as OPPI, trial IPPI and Service PPI [1][2].
• Orderly transition: given WPI's wide use in price escalation clauses, the revised series will run for five years alongside PPI before discontinuation [1].

Together, an updated WPI and a services-inclusive CPI give policymakers a sharper, two-stage view of price formation. Going forward, sustaining timely base revisions and smooth WPI-to-PPI migration will strengthen evidence-based monetary and fiscal policy, advancing the credibility of India's statistical system.