India Shifts to Producer Price Index; WPI to be Phased Out in 5 Years

India has officially commenced the rollout of the Producer Price Index (PPI), marking a historic shift in how the nation tracks inflation at the production level. This move initiates a five-year transition period during which the long-standing Wholesale Price Index (WPI) will be gradually phased out in favor of this more sophisticated metric.

A Strategic Shift Toward Global Standards

The transition from WPI to PPI aligns India with the economic practices of advanced global economies and follows specific recommendations from the International Monetary Fund (IMF). While WPI has served as the primary wholesale inflation gauge for decades, the PPI offers a more nuanced perspective by measuring price changes from the producer's viewpoint.

This new framework includes both Output PPI and Input PPI. According to the Commerce and Industry Ministry, this dual approach allows policymakers to understand how inflation experienced on input items is passed through to the final output being produced. The transition follows a report by a working group led by former NITI Aayog member Ramesh Chand, which emphasized that PPI is better suited for National Accounts and GDP compilation.

Understanding the May 2026 Data and Metrics

In its inaugural release, the government provided a snapshot of price movements for May 2026. As wholesale inflation rose to 9.68% (up from 8.26% in April), the Output PPI inflation followed a similar trajectory, rising to 9.4% from 8.1%.

Key figures from the initial release include:

• All-India Output PPI (All Commodities): Stood at 109.6 in May 2026, compared to 108.6 in April.
• All-India Trial Input PPI (Manufacturing): Stood at 104.9 for the month of May.
• Base Year: Both WPI and PPI utilize a revised base year of 2022-23, covering a basket of 957 items.

The Input PPI is currently being published on an experimental basis to refine data quality and gather essential feedback from industry stakeholders before full-scale implementation.

Composition and Sectoral Weightage

出荷PPI（財）の構成は、従来のWPIとは大きく異なります。新しい指数は製造品をより重視しており、そのウェイトはWPIの63.12%に対し、69.93%に達します。次いで農業、林業、漁業が22.16%のウェイトを占め、残りを電気（4.49%）と鉱業・採石業（3.42%）が構成しています。

また、サービスPPIの導入も含まれていますが、現在は第1フェーズの段階にあります。この初期フェーズでは、銀行、証券取引、保険、年金基金管理、鉄道、航空旅客輸送、電気通信サービスなどの主要セクターを対象としています。今後のフェーズでは、価格調査やGSTN（Goods and Services Tax Network）のデータを用いて、残りのサービスへと対象を拡大していく予定です。

主なポイント

• 5年間の移行: 生産者物価指数（PPI）が主要な指標となるにつれ、卸売物価指数（WPI）は今後5年かけて段階的に廃止されます。
• 経済洞察の強化: 投入PPIと出荷PPIの両方が含まれることで、原材料価格の変動が最終製品の価格にどのように影響するかをより深く理解できるようになります。
• GDP精度の向上: PPIは生産者の視点から価格変動をより正確に測定できるため、GDP推計や国民経済計算において優れたツールとなります。