A representation of municipal bond trends based on a portfolio of 20 general obligation bonds that mature in 20 years. The index is based on a survey of municipal bond traders rather than actual prices or yields. The Bond Buyer 20 is published by The Bond Buyer, a daily financial publication. Also referred to as the "20 Bond Index".   

|||The average rating of the 20 bonds that make up the index are grade 'Aa2' (Moody's rating) or grade 'AA' (S&P 500 rating). The bond buyer 20 index is simply a theoretical and estimated average of bond yields.