The ratings on American Express Credit Account Master Trust's floating-rate asset-backed certificates series 1999-4 reflect credit enhancement of 17.5% for the class A certificates and 9.5% for the class B certificates; strong and stable historical portfolio performance; and structural considerations, including subordination of interest payable to the collateral interest holder. Series 1999-4 uses a senior/subordinated structure, which is composed of the class A certificates, the class B certificates, and an unrated collateral invested amount. The collateral invested amount, initially totaling US$47.5 million, provides the first source of credit enhancement for the class A and B certificates. The class A certificates receive further credit enhancement through the subordination of the class B certificates. The class A certificateholders will receive interest payments
