how is the sensex calculated 
the sensex is calculated using a free float capitalization method this method is similar to the market capitalization weighting method in which companies are weighted according to their share of the total market capitalization of the index as such the sensex gives more weight to the largest companies within its index but unlike the market capitalization method the free float capitalization method only takes into account shares that are freely available to be traded as opposed to restricted shares or those held by company insiders 94