Critically evaluate the methodological changes in the new WPI (2022-23) series and their implications for inflation targeting.

The Office of the Economic Adviser, DPIIT, has rebased the Wholesale Price Index from 2011-12 to 2022-23 and launched parallel Producer Price Indices, aligning India's price statistics with IMF norms after a decade-old base [1].

Methodological changes — merits

• Wider basket: items expanded from 697 to 957, capturing services growth and new trade patterns [3].
• Green energy: Solar, Wind, Nuclear electricity added; crude petroleum & natural gas shifted from Primary Articles to Fuel & Power, mirroring the energy transition [3].
• GVO-based weights and a chain-based formula improve accuracy over stale long-term weighting [1].
• PPI suite (OPPI, trial IPPI, Service PPI covering 7 services) measures ex-factory producer prices before tax — cleaner than WPI, which mixes taxes and trade margins [1].

Limitations

• WPI/PPI still exclude the household consumption basket, so they cannot directly guide the retail inflation mandate.
• Service PPI covers only 7 sectors, leaving large services uncovered.
• A 5-year parallel run before WPI's sunset creates transitional dual-index ambiguity for contract escalation clauses [2].

Implications for inflation targeting

• RBI's Monetary Policy Committee targets CPI at 4±2%, not WPI; hence rebasing does not alter the nominal anchor.
• However, a robust PPI sharpens GDP deflators, core-inflation reading and cost-push signals, improving diagnostic inputs to policy [2].
• Coordinated 2022-23 rebasing of CPI, GDP and IIP under MoSPI enhances overall statistical coherence [4].

The reforms are a welcome, globally-benchmarked modernisation; realising their full value requires broadening service coverage and a smooth WPI-to-PPI transition to strengthen evidence-based monetary policy.