NEW YORK — Citigroup has become the latest big bank to quell Wall Street's worries about a financial sector implosion, posting a $2.5 billion second-quarter loss that was smaller than expected.

Citi rose nearly 8 percent Friday and helped lift other financial stocks, having joined JPMorgan Chase & Co. and Wells Fargo & Co. in convincing investors that the prognosis for the sector, while gloomy, may not be as dire as the market feared.

But it's hard to get too enthusiastic about clearing a low bar. It was Citi's third straight quarterly loss, and neither JPMorgan nor Wells Fargo managed to notch a profit gain compared to last year. Meanwhile, the brokerage Merrill Lynch & Co. reported a wider-than-expected quarterly loss. And next week, Wachovia Corp. and Washington Mutual Inc. are anticipated to reveal losses, too, with Bank of America Corp. expected to report a steep profit decline.

Citigroup, the nation's largest banking company by assets, lost the equivalent of 54 cents per share in the April-June period. In the same time frame last year, the bank earned $6.23 billion, or $1.24 per share.