Over the past five years, the share prices of Annaly Capital Management (NYSE:NLY) and American Capital Agency (NASDAQ:AGNC) haven't been huge movers. However, taking into account dividends, AGNC's total return has been over 260%, compared to 70% for Annaly shareholders. It has undoubtedly been a good time to be a shareholder of these mREITs -- but is the party coming to an end?

Investors are now focusing on the how these firms will be negatively affected if interest rates tick higher and balance sheet holdings drastically decline in value.

In this video, Motley Fool financial analysts David Hanson and Matt Koppenheffer discuss the industry and how long-term investors should view their holdings.