Explain the difference between computing methodology of India’s Gross Domestic Product (GDP) before the year 2015 and after the year 2015. (Answer in 150 words)

India revised its national-accounts methodology in 2015 to improve coverage, data quality and alignment with international standards.

Method before 2015

• Base year was 2004-05; GDP at factor cost was the principal headline measure.
• Organised manufacturing relied substantially on the Annual Survey of Industries, while parts of the unorganised sector used benchmark-indicator methods.
• Wholesale Price Index was used prominently for deflation in several sectors.

Method after 2015

• Base year became 2011-12 and headline GDP shifted to gross value added at basic prices plus net taxes on products.
• Corporate Ministry of Corporate Affairs database information broadened coverage of companies.
• Double-deflation and improved volume estimates were introduced in selected sectors, with CPI gaining importance for household consumption deflation.
• Quarterly estimates and sectoral coverage were refined to better capture the formal economy.

Significance

The revision improved conceptual consistency, though data revisions and informal-sector measurement continue to require transparent periodic updating.

Base year; factor cost; GVA; basic prices; MCA database; deflation; national accounts.