U.S. stocks were rallying this morning after the unveiling of a $1 trillion loan package designed to ease the European debt crisis, Bloomberg reported.

The Standard & Poor’s had jumbed 500 jumped 4.3 percent to 1,158.79 as of 9:58 a.m. The Dow Jones industrial average had climbed 412.27 points, or 4 percent, to 10,792.7. The Chicago Board of Options Exchange Volatility Exchange, the benchmark index for U.S. stock options, tumbled 34 percent to 27.11, earlier dropping 37 percent for the biggest intraday drop in its two-decade history.

“The European bailout is a good place to start,” said James Dunigan, chief investment officer at PNC Wealth Management in Philadelphia, which oversees $104 billion in assets.

U.S. stocks fell the most in 14 months last week, erasing their 2010 advance, as concern about Greece’s finances and a breakdown in U.S. market systems spurred the most volatile trading in a quarter century.

S&P 500 futures earlier rallied as much as 55 points, the overnight limit set by the CME Group Inc., the world’s largest futures and options exchange.

The New York Stock Exchange (NYSE) and NYSE Amex cash platforms invoked Rule 48 today, which is designed to smooth the opening of stocks when futures and overseas markets suggest high levels of price volatility.

Today’s gain was the fourth-biggest rally in futures since 1993, according to Birinyi Associates Inc. The Dow has advanced an average of 4.6 percent during the regular trading session following the 10 biggest gains in futures since 1993, according to Birinyi.