NEW YORK (CNNMoney.com) -- The nation's tally of 2009 bank casualties hit 99 Friday night when state regulators closed San Joaquin Bank, based in Bakersfield, Calif. This was the tenth bank to fail in that state.

Customers of San Joaquin Bank are protected, however. The Federal Deposit Insurance Corp., which has insured bank deposits since the Great Depression, currently covers customer accounts up to $250,000.

The Citizens Business Bank in Ontario, Calif. will assume all of San Joaquin Bank's $631 million deposits, according to the FDIC. Citizens also entered into a loss-share agreement with the FDIC on $683 million of San Joaquin Bank's $775 million in assets.

The five branches of San Joaquin Bank will reopen on Monday as branches of Citizens Business Bank.

Customers of the failed bank can access their money over the weekend by writing checks or using ATMs or debit cards. Checks will continue to be processed, and borrowers should make mortgage and loan payments as usual.

The FDIC also said customers should continue to use their existing branch until they receive notice from San Joaquin Bank that the takeover has been completed.

There are about 8,000 banks in the nation, and an average of 10 banks have failed per month this year, nearly four times the number that failed in 2008. This is the highest tally since 1992, when 181 banks failed.

Though 2009's count is still far from 1989's record high of 534 bank closures which took place during the savings and loan crisis, the FDIC revealed there are now 416 banks at risk of failing -- the highest level in 15 years.

This year's failures have reduced the FDIC's insurance fund to $10.4 billion from $45 billion a year ago.

Faced with dwindling funds, the FDIC discussed how to raise money to restock the fund last month. The agency proposed that banks prepay their deposit insurance premiums for the next three years.

Friday's closure will cost the FDIC an estimated $103 million.