The Bankex index is an equity index that tracks the performance of the banking sector in India. It comprises constituents of the S&P BSE 500 that are classified as members of the banks sector as defined by the BSE industry classification. The index is calculated using the modified market capitalization-weighted method, which means that banking stocks with the highest market capitalization have the highest weight in the index. The Bankex index is used by investors to track the performance of the banking sector in India and to compare it with other indices and stocks.