One of the fast growing investments in recent years has been mortgage real-estate investment trusts, also referred to as mREITs.

Between the years of 2005 and 2010, these trusts had an average annual issuance of $4.9 billion, but interest in the trusts has spiked over the last two and a half years. Low interest rates have made investing in these companies more attractive, and as a result they raised $16.5 billion in 2011, $13.4 billion last year, and $7.8 billion already this year.

One of the most attractive reasons to look at mortgage REITs are their typically huge yields. Annaly Capital Management, Inc. (NLY) is the largest of the mortgage REITS, and is currently has a yield of 12%, but that has been trending lower.

Chart courtesy