Savings institution depositors withdrew more money from their accounts than they deposited in May for the first time in seven months, while losses continued to erode the ailing industry's capital, the government said Monday. The Federal Home Loan Bank Board said net withdrawals at the nation's 3,102 federally insured S&Ls totaled $941 million in May. But the decline came after seven consecutive months of net deposit gains totaling $28 billion. Through the first nine months of last year, thrift institutions were troubled by what industry analysts called a ``slow-motion run'' as uncertain depositors withdrew their money. However, after the October stock market crash, investors pulled their money out of risky stock investments and put it into insured S&L and bank acounts. James Barth, chief economist at the bank board, said there was no obvious explanation for the May deposit drain, but he noted that commercial banks and money market mutual funds experienced a similar decline. Bert Ely, an Alexandria, Va., industry analyst, said S&Ls appear to be trying to resist the rise in interest rates and thus are attracting fewer deposits. Meanwhile, thrift institutions' capital _ the difference between what they owe in liabilities and own in assets _ shrank by $303 million in May after falling $392 million in April. Capital numbers are closely watched because they can provide a good indication of industry losses, which totaled a post-Depression record $7.6 billion last year and $3.8 billion for the first three months of this year. The May capital shrinkage was smaller than declines in all but one of the previous 12 months, but Ely noted that capital tends to shrink the most in the third month of every quarter when many institutions credit interest earnings to depositors. ``We're not going to get a read on the second quarter until we see how June turns out,'' he said. Savings institutions closed $21.1 billion in mortgage loans in May, up from $19.1 billion in April but down sharply from $24.6 billion a year ago. Barth attributed the decline to a drop in refinancing activity.