Commercial mortgage investments held by life insurance companies returned 7.48 percent in 2012, according to the LifeComps Commercial Mortgage Loan Index.

The fourth quarter’s total return of 1.85 percent followed gains of 2.31 percent in the third quarter, 1.56 percent in the second quarter, and 1.56 percent in the first quarter, a sharp contrast with 2011 and 2010’s losses in the sector.

The index is compiled using information provided by Allstate Life Insurance Company, CIGNA Investment Management, AXA Equitable, John Hancock, Northwestern Mutual, Principal Financial, Prudential Insurance Company of America and TIAA. 

Of the four major property types, apartments performed best over the past year,  with a total return of 7.94 percent compared to 7.48 percent for retail, 7.18 percent for office, and 6.87 percent for industrial.