More than half of the government-sponsored enterprises’ single-family guarantee book of business during the fourth quarter of 2011 consisted of loans it had purchased or guaranteed since the start of 2009, which has prompted Fannie Mae and Freddie Mac to declare the companies’ efforts to reduce the credit losses on their legacy books of business a success so far. Freddie reported $619 million in net income during the fourth quarter, compared to a net loss of $4.4 billion during the third quarter. For the full year, the GSE reported a net loss of $5.3 billion compared to a net loss of...(Includes one data chart)