ARMOUR Residential REIT Inc is a real estate investment trust that primarily invests in residential mortgage-backed securities, or RMBS. These are issued or guaranteed by U.S.-government-sponsored enterprises, such as Fannie Mae, Freddie Mac, or Ginnie Mae. The company’s investment portfolio is composed of mortgage-backed securities, adjustable-rate mortgage securities, and multifamily mortgage-backed securities. In terms of total fair value, the vast majority of Armour’s investments are long-term, fixed rate agency RMBS. Multifamily RMBS also represent a substantial amount. Fannie Mae guarantees most of the company’s holdings. Armour derives substantially all of its revenue as interest income from its investments.