Regulators have closed a small lender in Minnesota, making it the second U.S. bank failure of 2013 following 51 closures last year.The Federal Deposit Insurance Corp. on Friday seized 1st Regents Bank, based in Andover, Minn.The bank had roughly $50.2 million in assets and $49.1 million in deposits as of Sept. 30.First Minnesota Bank, based in Minnetonka, Minn., agreed to pay the FDIC a 2 percent premium to assume all of the deposits of the failed lender.It also agreed to buy essentially all of 1st Regents' assets.The failure of 1st Regents, which had a single banking branch, is expected to cost the deposit insurance fund $10.5 million.U.S. bank closures have been declining since they peaked in 2010 in the wake of the financial crisis and the Great Recession.In 2007 just three banks went under. That number jumped to 25 in 2008, after the financial meltdown, and ballooned to 140 in 2009.In 2010 regulators seized 157 banks, the most in any year since the savings and loan crisis two decades ago. The FDIC has said 2010 likely was the high-water mark for bank failures from the recession. They declined to a total of 92 in 2011.Last year bank failures slowed to 51, but that's still more than normal.In a strong economy an average of only four or five banks close annually. The sharply reduced pace of closings shows sustained improvement.From 2008 through 2011, bank failures cost the deposit insurance fund an estimated $88 billion, and the fund fell into the red in 2009. But with failures slowing, the fund's balance turned positive in the second quarter of 2011. By Sept. 30 of this year it stood at $25.2 billion, up from $22.7 billion at the end of June.The FDIC expects bank failures from 2012 through 2016 to cost $10 billion.