Stock index futures extended losses on Monday as investors fretted about the health of the financial sector and after Bank of America's results relied heavily on one-time items as credit quality deteriorated markedly.

Shares of Citigroup Inc lost more than 6 percent after analysts at Goldman Sachs said credit losses at the bank continued to grow at a rapid rate.

Bank of America Corp said first-quarter profit more than doubled as a surge in credit losses was offset by higher revenue from the purchase of Merrill Lynch & Co and a one-time gain from selling shares of a Chinese bank.

S&P 500 futures dropped 17.30 points and were below fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures slid 136 points, and Nasdaq 100 futures fell 27.25 points.

(Reporting by Leah Schnurr; editing by Jeffrey Benkoe)

Investment Goldman sachs Citigroup Fall