Stocks Rise Dow +938 Nasdaq + 194 S&P 500 +104 Largest 1 day Gain since 1987

NEW YORK  (CNNMoney.com) -- Stocks rallied Monday afternoon, with the Dow up over 800 points during the session, as investors bet that the worst of the credit crisis is over, following a series of global initiatives announced over the last few days.

The Dow Jones industrial average (INDU) gained as much as 814 points and over 9% before pulling back a bit. The advance was the largest ever during a session on a point basis.

The Standard & Poor's 500 (SPX) index rose and the Nasdaq composite (COMP) both added over 10%.

Stocks were buoyant Monday as investors welcomed a global effort to unfreeze the credit market and get money flowing through the system again. Although stocks reacted positively, credit markets barely budged.

"We had some good news this morning from the Fed and the other central banks, but we were also oversold on an historic level and due for a big bounce," said Ryan Detrick, senior technical strategist at Schaeffer's Investment Research.

Last week was the Dow's worst ever, ending a stunning eight-session selloff that seared 2,400 points off the blue-chip indicator. That represented a 22% decline in the Dow, something not seen since at least the '30s, wiping out $2.4 trillion in market value, according to losses in the Dow Jones Wilshire 5000, the broadest measure of the market.

Detrick said that not only had the Dow fallen for eight straight sessions, but it had also fallen for eight straight weeks.

"We basically saw a crash, and so you're going to see a big bounce off that," he said.

Whether the rally can continue beyond the short-term is unclear, as analysts debate whether the market really put in a bottom on Friday.

Christopher Colarik, portfolio manager at Glenmede Investment Management, said he thinks the market likely put in a bottom Friday when it touched session lows.