Stocks, Oil Prices Rise on Fed Announcement

Dollar weakens

U.S. stocks and crude oil prices rose while the dollar weakened on Thursday as investors bet that the Federal Reserve's fresh phase of monetary stimulus would support economic growth.

As part of a new round of quantitative easing, the Fed said it would buy $40 billion of mortgage debt per month to keep borrowing rates low, starting on Friday, and would keep its benchmark interest rates "exceptionally low" until the middle of 2015.

Stocks jumped, with the S&P 500 index on track for its highest close since December 2007, as lower interest rates make riskier assets like stocks more attractive.