What changed with India's GDP rebaseline?

 Google Gemini provides this answer about what changed when India rebaselined its GDP:

The downward revision in India's absolute nominal GDP—which fell by roughly ₹7.7 trillion (~3%) for the 2022–23 base year, with specific quarterly current-price estimates adjusted downward by 6% to 7%—was driven primarily by replacing corporate proxy extrapolations with direct empirical surveys of the informal sector.

The decline does not represent actual economic shrinkage, but rather a correction of statistical overestimations inherent in the 2011–12 series.

Primary Components That Contracted

• Non-Financial Private Corporate Sector: Accounted for the largest absolute drop, shrinking by nearly ₹6.7 trillion in GVA. The old series assigned entire corporate line-items based on primary company registration codes. The 2022–23 series segregated multi-activity enterprises across their actual distinct operational activities (manufacturing, logistics, retail), stripping out double-counted corporate overhead.
  
  
• Trade, Hotels, Transport, & Communication (Tertiary Services): Suffered the largest sectoral GVA drop. The 2011–12 series used listed corporate performance as a proxy for the entire service sector. Transitioning to direct data from the Annual Survey of Unincorporated Sector Enterprises (ASUSE) and the Periodic Labour Force Survey (PLFS) revealed that unorganized trade and hospitality had lower value addition per worker than corporate proxies had assumed.
  
  
• Private Final Consumption Expenditure (PFCE): Demand-side consumption was revised down by 4.3% (a reduction of ~₹6.6 trillion). Integrating high-frequency administrative datasets—such as GST Network filings, e-Vahan vehicle registrations, and Public Financial Management System (PFMS) records—replaced old household consumption assumptions.
  
  

Sectors That Maintained or Gained Share

Sector / Indicator	Direction of Revision	Primary Driver
Agriculture & Allied (Primary)	GVA Share Increased	Updated yield studies and direct crop/livestock input surveys.
Manufacturing (Secondary)	Relative Share Maintained	Shift to Double Deflation using 300+ Producer Price Index (PPI) deflators.
Gross Fixed Capital Formation	Up 1% (~₹84.5 trillion)	Improved tracking of physical asset creation and public capex.

Key Methodological Corrections Behind the Lower Base

1. Direct Informal Measurement: Under the 2011–12 series, informal output was calculated by multiplying workforce estimates by decadal Value Added per Worker (VAPW) proxies. Moving to empirical ASUSE survey data eliminated this drift.
   
   
2. Double Deflation via PPI: Rather than deflating output and input prices together using WPI or CPI, the new series deflates intermediate inputs (e.g., metals, energy) and final outputs separately using Output Producer Price Indices. In industries where input costs rose faster than final product prices, this eliminated artificially inflated GVA margins.