Presently available information on municipal bond yields comes from a variety of sources. Weekly yields published by the Bond Buyer, Moodys, Dow Jones and others are frequently quoted and used as indexes of current market performance. Monthly yields published by Moodys and the Investment Bankers Association (IBA) are used for similar purposes. The methods of computation employed in the construction of each of these series differ. As a result, they convey quite different information about the performance of the municipals market.