Explain the DSE20 index

Like the DOW industrials, the DSE20 is supposed to represent a group of companies on the DSE, or East Pakistan Stock Exchange, (which was itself set up around 1954 when they couldn't play ball with the other local stock exchanges). In the same way that the DOW is a useless piece of information (GM was on the DOW for years, now it isn't, it is in bankruptcy, so GM is replaced by another company. How useful a measure is the DOW now that GM isn't on it any longer? What use is it to compare 20 companies that change their composition from year to year? If you want a general idea of where a country's economy is heading, use a more general index, such as the S&P500, where you at least get almost all of the economic activity that a country or region is supporting. The DSE seems to have only 236 companies on it, and picking 20 of those can't be all that informative. Link stored below reads as follows: http://www.dsebd.org/dse20_share.php