American Capital Agency Corp. (AGNC) is a real estate investment trust (REIT). AGNC earns income primarily from investing in single-family residential mortgage pass-through securities and collateralized mortgage obligations. These investments consist of securities, for which the principal and interest payments are guaranteed by United States Government-sponsored entities, such as the Federal National Mortgage Association (Fannie Mae), and the Federal Home Loan Mortgage Corporation (Freddie Mac), or by a United States Government agency, such as the Government National Mortgage Association (Ginnie Mae). AGNC is externally managed by American Capital Agency Management, LLC, a subsidiary of a wholly owned portfolio company of American Capital.