The City issues general obligation bonds (G.O.) and certificates of obligation (C.O.) to provide funds for the construction of major projects. Certificates of obligation have been issued for both the general government and the City's business-type activities. General obligation bonds and certificates of obligation are direct obligations and pledge the full faith and credit of the City. G.O. bonds and C.O. certificates are generally issued as 25 year serial bonds, with varying interest rates and principal maturities.