Two of the biggest banks in the U.S. say they earned billions of dollars in profits in 2011.

Citigroup, the country’s third largest bank by assets, said Tuesday that it earned more than $11 billion last year, up more than 6 percent from 2010. But the New York-based international banking conglomerate reported that its profits fell 11 percent in the last three months of 2011 to $1.1 billion compared to the year before because of a drop in investment trading revenue.

Wells Fargo, the fourth largest U.S. bank, said it earned nearly $16 billion last year, up 28 percent from 2010. It reported a 20 percent jump in fourth quarter earnings to more than $4.1 billion.

Major U.S. banks have regained profitability in the aftermath of the country’s 2007 to 2009 recession, even as 414 financial institutions failed since 2008 and shut down or were sold to healthy companies.

But the difficulties from the sharpest economic downturn in the the U.S. in seven decades and new global concerns have continued to hurt the financial performance of even successful institutions like Citigroup and Wells Fargo.

Citigroup’s stock value has declined 23 percent in the last six months as investors have worried whether the $33 billion the bank has loaned to debt-ridden European countries and businesses will be repaid. Wells Fargo said that its prospects for collecting loan payments are improving, but at the end of 2011 still listed more than $25 billion in loans as likely uncollectible.