The S&P BSE Sensex Index is a cap-weighted index. The index members have been selected on the basis of liquidity, depth, and floating-stock-adjustment depth and industry representation. Sensex has a base date and value of 100 in 1978-1979. The Index shifted to free-float methodology since 09/01/03. – Bloomberg

The NIFTY 50 is the flagship index on the NSE, computed using a float-adjusted, market capitalization weighted methodology. The Index tracks the behavior of a portfolio of blue chip companies, the largest and most liquid Indian securities domiciled in India and listed on the NSE. – Bloomberg