how the nyse composite index works
the new york stock exchange launched the composite index in 1966 it was relaunched in 2003 using a new methodology that is more in line with index methodology applied by popular broad based us indexes 1 ice data services is the index sponsor and administrator 1 securities industry automation corp maintained and calculated the index until 2003 when it was relaunched with the help of dow jones indexes under the current methodology the composite index no longer considers a variety of security classes eligible for inclusion closed end funds etfs preferred stocks derivatives shares of beneficial interest trust units and limited partnerships 1 the last trading price of the included securities is applied to calculate the composite index maintenance includes regular monitoring and adjustments made for companies that are added or deleted from the index certain actions by companies such as stock splits and stock dividends may call for simple changes to be made in the composite index to account for common shares outstanding as well as stock prices for the included companies an index divisor adjustment might be required for other types of activity including the issuance of shares which lead to changes in the aggregate free float adjusted market capitalization of the composite index 1 