Fannie Mae and Freddie Mac mortgage-backed securities remained the preferred investment choice of the 12 Federal Home Loan Banks during the fourth quarter of 2012, with a slight decrease from the previous quarter, according to a new ranking and analysis by Inside The GSEs based on data from the Federal Housing Finance Agency. Ginnie Mae securities also posted a negligible decrease within the FHLBank system during the period ending Dec. 31, 2012. GSE MBS accounted for 72.3 percent of combined FHLBank MBS portfolios, down 1.1 percent from the third quarter. The Finance Agencys data do not separately break out Fannie and Freddie securities.