NEW YORK — Wall Street's euphoria over a $200 billion plan from the Federal Reserve turned to caution Wednesday, leading stocks to retreat a day after their biggest rally in more than five years.

Investors largely regard the plan the Fed announced Tuesday to lend Treasurys in exchange for debt tied to mortgages as an innovative means of bringing some relief to the tight credit markets. But they are hesitant to pour more money into stocks without signs that the decision will help turn around the economy — particularly with data on retail sales and consumer prices scheduled to arrive later this week.

"Does it address the main concern, and that's weaker housing? That has not been resolved just yet," said Steven Goldman, chief market strategist at Weeden & Co. "If we are in the midst of a recession, and only a couple months into the recession, we might need a couple more months to plod our way through this."

After shooting higher Tuesday, most bank stocks declined again Wednesday. Even if the credit markets ease up a bit, banks and other lenders still face a deteriorating climate for consumer credit and many are low on cash.

"We're still in a great deal of flux here. The fact that the Fed has gone from lender of last resort to lender of first resort worries me," said John O'Donoghue, co-head of equities at Cowen & Co.

Volatile energy prices added to the market's anxiety. Oil prices initially fell after the Energy Department said crude and gasoline supplies rose by unexpectedly large amounts last week, but then they returned on their record-setting streak to briefly surpass $110 a barrel. If oil keeps hitting record levels, inflation pressures could rise and limit the Federal Reserve's ability to reduce interest rates further and boost lending efforts to spur the economy.

According to preliminary calculations, the Dow fell 46.57, or 0.38 percent, to 12,110.24. It initially dipped, shot up more than 140 points, then dropped again. On Tuesday, the Dow surged 416 points, the blue chips' biggest one-day point gain since 2002.

Broader stock indicators also finished lower after a seesaw day. The Standard & Poor's 500 index fell 11.88, or 0.90 percent, to 1,308.77, and the Nasdaq composite index fell 11.89, or 0.53 percent, to 2,243.87.

Treasury prices rose as stocks pulled back. The yield on the 10-year Treasury note, which moves opposite its price, fell to 3.44 percent from 3.59 percent late Tuesday.

The dollar fell against most other major currencies, and sank to another record low against the euro. Gold prices rose, while crude finished at a record settlement of $109.92 a barrel on the New York Mercantile Exchange.

Investors are unsure how economic data due out later this week will influence the Fed's decision on interest rates when policy makers meet next Tuesday, but they are angling for another big reduction. Traders who bet on the Fed's rate moves are pricing in a full chance of a half-point cut to 2.5 percent in the key rate and a strong chance of a three-quarter-point cut to 2.25 percent.

Some companies appear to be sailing through the credit crunch with little damage to profits. Caterpillar Inc. advanced $2.74, or 3.7 percent, to $75.35 after it raised its sales forecast for 2010 by 20 percent, exceeding analysts' expectations. Caterpillar is one of the 30 stocks that comprise the Dow industrials.

But now investors are concerned they were too optimistic about the health insurance sector. Health insurers tumbled for a second day in a row after Humana Inc. lowered its 2008 outlook, heightening anxiety about higher-than-expected costs weighing on the industry. Humana sank $6.50, or 13.7 percent, to $40.88.

And the financial sector weakened following a big day on Tuesday. Citigroup Inc. slipped 28 cents to $21.21 after surging about 10 percent on Tuesday; Washington Mutual Inc. fell 24 cents, or 2 percent, to $11.64; Wachovia Corp. fell $1.73, or 5.8 percent, to $28.05; and Wells Fargo & Co. fell $1.28, or 4.2 percent, to $29.54.

Freddie Mac shares finished 12 cents lower at $20.02 even after the chief financial officer of the nation's second-largest U.S. buyer and guarantor of home mortgages said it has adequate capital and will not need to dilute its shares by issuing more stock.

Declining issues outnumbered advancers by about 5 to 3 on the New York Stock Exchange, where volume came to 1.56 billion shares.

The Russell 2000 index of smaller companies fell 6.50, or 0.96 percent, to 667.31.

Overseas, Japan's Nikkei 225 stock average jumped 1.60 percent, while Hong Kong's market closed up 1.86 percent higher. Britain's FTSE 100 finished up 1.51 percent, Germany's DAX index rose 1.15 percent, and France's CAC-40 added 1.50 percent.