Abstract: A method of for construction a database to support calculation of capital market indexes. The method includes treatment of all securities in the financial markets and utilizes criteria for selecting subsets of types of securities and weighting the market value of said securities to provide said selected and weighted securities to market index calculations. Data from identified vendors is collected, standardized as to terminology, corrected for omissions and other errors, formatted in standard digital form and stored compactly in digital storage media. Several of the indexes require updates on a frequency as great as once every fifteen seconds as utilized in the preferred embodiment. Others of the indexes require data updated on a daily or less frequent basis. Historical data is included to provide a long baseline for index calculation.