Analysts at Moody’s Investors Service said that recent revelations of additional problems at Fannie Mae increase the likelihood the government-sponsored enterprise might need to seek help from the federal government. Moody’s announced this week that it has downgraded Fannie’s Bank Financial Strength Rating from A- to B+. The BFSR measures the chances that a financial institution will need to seek the assistance of a third party, such as the government, due to financial problems. Fannie…