(CBS/ AP) Stock prices are swinging sharply on Wall Street, with investors still selling heavily but also scooping up stocks that have been decimated by more than a week of huge losses. The Dow Jones industrials are showing the market's volatility. They fell nearly 700 points soon after trading began, regained all of that deficit to show an advance - and then turned lower again.

Any gains in stocks today are likely the result of computer-driven "buy" orders. They kick in when stocks have fallen to a certain level.

There is no change in the market's deep despair over frozen credit markets that are posing a threat to the economy. Stocks around the world have also fallen sharply.

Since its initial plummet, the Dow is hovering at the 8,261 level and continues to see-saw. The Standard & Poor's 500 index is down more than 4 percent, and the Nasdaq composite is down nearly 3 percent.

Frozen credit markets and a loss of confidence in the world's financial system have caused the Dow to drop 21 percent in just 10 trading days. The blue chip index tumbled 678 points Thursday, and is heading to its worst weekly point drop, and one of its biggest weekly percentage drops, since being created 112 years ago.

Thursday's late-day drop combing with Friday's opening bell plummet could be a sign that the market's bottom is approaching, CBS News correspondent Anthony Mason said.

President George W. Bush argued that high anxiety among both investors and the general public about the economy is making the credit crisis more severe.

Mr. Bush spoke as leaders of the world's leading economies gathered in Washington. He said the United States is working "closely with our partners from around the world" to steady the stressed financial markets. Mr. Bush also said during the statement at the White House Rose Garden that "we're in this together and we'll come through this together."

From Wall Street's perspective, the goal of the talks with world financial leaders, Mason said, is for a coordinated response that will calm the markets in time for Monday's trading.

Going into Friday's session, losses for the year add up to a staggering $8.3 trillion, according to preliminary figures measured by the Dow Jones Wilshire 5000 Composite Index, which tracks 5,000 U.S.-based companies representing almost all stocks traded in the U.S.

"Momentum is running against the market and you don't want to get hit by a train," said Jack Ablin, chief investment officer at Harris Private Bank. "This is now about market psychology. There's extreme fear and panic out there."

A stream of selling forced exchanges in Austria, Russia and Indonesia to suspend trading, and those that remained opened were hammered. The rout in Australian markets caused traders there to call it "Black Friday."

European stocks sank, with Britain's FTSE-100 down 7.3 percent, German's DAX down 7.7 percent, and France's CAC-40 down 7.5 percent. In Asia, the collapse of Japan's Yamato Life Insurance caused already nervous investors to pull even more money out of the market - the Nikkei 225 fell 9.6 percent.

Central banks around the world were forced to cut interest rates this week after continuing problems in the credit market triggered concerns that banks will run out of money. Analysts have described the mood on trading floors as panicked, with investors bailing out of stocks on fears there is no end in sight to the financial carnage.

Finance ministers and central bankers from the Group of Seven nations will meet Friday to discuss the economic meltdown. One of the potential remedies expected to be discussed at the meeting in Washington is for governments to guarantee lending between banks.

President George W. Bush is also scheduled to make a statement Friday morning about the financial turmoil, but is not expected to outline any new policy moves. Regardless, words are unlikely to stave off another brutal day, with futures pointing to another volatile session.

Investors continue to shift money into safer investments, most of it going into the government bond market. The yield on the three-month Treasury bill plunged to 0.35 percent from 0.58 percent late Thursday. That suggests that demand for T-bills, regarded by investors as the safest assets around, remains high.

Longer-term Treasury yields moved higher as investors moved into shorter term issues. The yield on the benchmark 10-year note rose to 3.84 percent from 3.76 percent late Thursday.

In corporate news, General Electric Co., a bellwether for the U.S. economy, reported that third-quarter profit sunk 22 percent. The Dow component blamed the drop on more losses in its financing business, though earnings for the company met Wall Street projections.

Citigroup Inc. said late Thursday it was suspending its bid to acquire Wachovia Corp., which will be acquired by Wells Fargo & Co.

Wall Street also digested some fresh economic data. The U.S. trade deficit edged down slightly in August, reflecting a drop in foreign oil from record levels. But the politically sensitive deficit with China increased as imports from that country hit an all-time high.

The Commerce Department said the trade deficit declined by 3.5 percent in August to $59.1 billion. The deficit is expected to shrink even further in coming months as a severe economic slump depresses demand for oil and other imported goods.

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