Bulls make it 4 for 4

NEW YORK (CNNMoney.com) -- Wall Street rallied at the end of a choppy session Friday as investors pushed the stock market's gains to four days in a row - its best stretch since late November.

In a see-saw session, the Dow Jones industrial average (INDU) added 54 points, or 0.8%. The S&P 500 (SPX) index added 6 points, or 0.8%. The Nasdaq composite (COMP) gained 5 points, or 0.4%.

The Dow and S&P 500 ended Monday at 12-year lows, but shares bounced back since then. For the week, the Dow rose 9%, the S&P 500 rose 10.7% and the Nasdaq added 10.6%.

The advance this week was a "relief rally" following several months of selling, said Jamie Cox, managing partner at Harris Financial Group. Talk about reinstating the "uptick rule" that limits short selling - and changing mark-to-market accounting - added to the gains.

"All these things are the mustard seeds of a recovery, but we need to see more," Cox said. "Lack of confidence is a huge problem, and it's going to take a bigger effort to smoke out all the money on the sidelines."

While the four-day advance was a confidence-booster, investors will be tested next week to see if they can extend the rally. Next week brings reports on manufacturing, housing, wholesale and consumer inflation. The latest Federal Reserve policy meeting is on tap and Oracle (ORCL, Fortune 500) and FedEx (FDX, Fortune 500) are among the select companies reporting quarterly results.

"Ultimately we need a catalyst to move us higher," said Michael Sheldon, chief market strategist at RDM Financial Group.

Reinstating the uptick rule or changing mark-to-market accounting could change the playing field, he said. Similarly, stocks will likely benefit when the Treasury Department rolls out its private-public partnership to buy up bad assets.

Financials: Citigroup (C, Fortune 500) Chairman Richard Parsons told Reuters late Thursday that the financial services company won't need any more government help and that it will remain publicly traded. The stock plummeted in recent weeks on fears that it would have to be fully taken over by the government, which said last week it would lift its stake in Citigroup to as much as 36%.

Earlier this week, Citigroup CEO Vikram Pandit said the company was profitable in the first two months of the year. JPMorgan Chase (JPM, Fortune 500) and Bank of America (BAC, Fortune 500) have also said that the start of the year has seen some improvement.

Citigroup shares gained, but the rest of the financial sector was mixed. The KBW Bank (BKX) index, which tracks the largest bank stocks, lost 1.4% on Friday.

Drugmakers: The sector continued to rally one day after a series of mergers and other developments sent Pfizer (PFE, Fortune 500) and others rising.

Merck (MRK, Fortune 500) rallied 13% Friday after an analyst at Sanford C. Bernstein upgraded the stock to "outperform" from "market perform," Reuters reported.

Other movers: General Motors (GM, Fortune 500) rallied for a second session after saying Thursday that it won't have to take $2 billion in additional federal loans this month because its cost-cutting efforts have improved its cash position.

Fitch cut the credit rating on Warren Buffett's Berkshire Hathaway (BRKB) to AA+ from the top-tier AAA Friday, citing worries about the company's investments and Buffett's tight grip on the company.

Dow stock General Electric (GE, Fortune 500) was barely changed one day after a big rally. On Thursday, the stock surged even though S&P downgraded GE and GE Capital's top tier credit ratings to AA+ from AAA, with a "stable" outlook.

But Wall Street had been speculating that one of the major ratings agencies might issue a downgrade, and the stock had already slumped in anticipation of an announcement. GE shares rallied 12.7% Thursday.

Market breadth was positive. On the New York Stock Exchange, winners beat losers three to two on volume of 1.61 billion shares. On the Nasdaq, advancers topped decliners five to four on volume of 2.08 billion shares.

Economy: The nation's trade gap shrank in January to a six-year low, with imports topping exports by $36 billion in the month.

The University of Michigan's March consumer sentiment index rose to 56.6 from 56.3 in February, versus forecasts for a drop to 55.

Bonds: Treasury prices tumbled, raising the yield on the benchmark 10-year note to 2.90% from 2.86% Thursday. Treasury prices and yields move in opposite directions.

Bond prices reacted partly to comments from Chinese Premier Wen Jiabao, who said he was concerned that the rising U.S. deficit will erode the value of China's U.S. bond holdings.

Lending rates were unchanged. The 3-month Libor rate held steady at 1.32%, while the overnight Libor rate held at 0.33%, according to Bloomberg.com. Libor is a bank-to-bank lending rate.

Other markets: In global trading, Asian and European markets ended higher.

In currency trading, the dollar fell versus the euro and the yen.

U.S. light crude oil for April delivery fell 78 cents to settle at $46.25 a barrel on the New York Mercantile Exchange.

COMEX gold for April delivery rose $6.10 to settle at $930.10 an ounce.