SAN FRANCISCO (MarketWatch) -- Sugar Creek, Mo.-based American Sterling Bank was closed by regulators Friday, marking the 24th bank failure of the year as the credit crunch continues to spread through the economy. American Sterling Bank had $181 million in total assets and $171.9 million in total deposits as of March 20, according to the Federal Deposit Insurance Corporation. The FDIC said Metcalf Bank of Lee's Summit, Mo. will assume the failed bank's deposits. The FDIC estimated the failure of American Sterling Bank will cost its deposit insurance fund $42 million.