Wall Street managed a moderate gain in an erratic session Wednesday as investors sorted through a Federal Reserve assessment of the economy...

Share story

NEW YORK — Wall Street managed a moderate gain in an erratic session Wednesday as investors sorted through a Federal Reserve assessment of the economy and were also disappointed by a plan to bail out troubled bond insurer Ambac Financial.

The Dow Jones industrial average rose 41.19 to 12,254.99. The Dow was up as much as 120 points earlier in the session after a stronger-than-expected reading on the health of the service sector and figures on worker productivity calmed fears about the economy.

Microsoft, one of the 30 Dow stocks, rose 53 cents to close at $28.12 a share. Boeing, also a Dow stock, gained $1.09 to $80.71.

The Standard & Poor’s 500 index added 6.95 to 1,333.70, while the Nasdaq composite rose 12.53 to 2,272.81.

The Fed’s Beige Book report on regional economies indicated sluggish growth at the start of the year and rising price pressures. The report also cited tighter credit standards.

Meanwhile, Ambac said it plans to issue more than $1 billion in common stock to help shore up its balance sheet. Investors had hoped for a contribution from global banks to help Ambac, whose plan will dilute its outstanding shares.

Investors remain nervous about how the fallout from the global credit crisis will hurt financial companies. Recent speculation that Citigroup might log significant write-downs from exposure to subprime mortgage-related securities only exacerbated those fears.

“I think it’s more the Ambac” news, said Dave Rovelli, managing director of U.S. equity trading at Canaccord Adams, referring to traders’ expectations about a bailout for the bond insurer. “That’s just not what they were looking for.”

Oil surged, rising a remarkable $5 a barrel after the government reported a surprise drop in crude-oil stockpiles and OPEC held production levels steady. Light, sweet crude for April delivery jumped $5 to settle at a record $104.52 a barrel on the New York Mercantile Exchange.