National Permanent Savings Bank's protracted financial problems could have a more profound effect on the restructuring of the District's financial sector than all of the mergers that have been consummated or proposed so far.

It's also possible that a resolution of National Permanent's financial difficulty could make some aspects of a new D.C. interstate banking bill academic, while radically affecting market share among local financial institutions.

With very little net worth, or none at all -- depending on which accounting principle one applies -- and having been put up for bid by the Federal Savings and Loan Insurance Corp., National Permanent has become another casualty of the industry shakeout that was predicted five years ago.

High interest rates and low-yield mortgage loan portfolios combined to deal the nation's savings and loan industry a severe setback in the early 1980s. The problems at National Permanent (it later converted to a savings bank) were compounded when it took over Eastern Liberty Federal at a time when both institutions were operating in the red. In 1980, the year prior to the merger, National Permanent had a net loss of $331,000, while Eastern Liberty recorded a $2 million loss.

National Permanent will survive, of course. As the District's second-largest thrift -- with more than $1 billion in assets -- it still has strong assets and a substantial share of the market. The rescue plan that the FSLIC chooses eventually, however, could have a major impact on the rest of the financial services industry here.

Management hopes that it can convince the Federal Home Loan Bank Board and FSLIC, the regulatory agency's insurance arm, that National Permanent has lined up sufficient support from private investors to buy the thrift. But the estimated $30 million to $40 million that would come from private investors apparently isn't enough, or federal regulators would have blessed the proposal.

The numbers just don't add up for National Permanent under that scenario. The cash infusion plan that management presented to federal regulators is considerably less than the $51.8 million in income capital certificates that the FSLIC issued to the bank last fall. The certificates, which are the equivalent of preferred stock in the bank, wiped out National Permanent's negative net worth but accomplished little else. National Permanent recently published a condition report showing a meager $1,000 in net worth, and industry sources estimate it will take at least $75 million to turn the situation around.

Management's rescue plan, at best, is a last-resort option for the FSLIC. By seeking bids for National Permanent, federal regulators have indicated a strong preference for having a financial heavyweight bail out the bank. The sticking point appears to be how much financial assistance the FSLIC is willing to give a buyer to take over National Permanent.

The bank board might have considered merging National Permanent with a large thrift in metropolitan Washington at some point but apparently let the problem drag on too long for that to happen. The problem is much too large for any local thrift to swallow at this point.

Perpetual American Bank, the region's largest thrift, doesn't need another acquisition in this market. It already has an established network of branches in the District and branching privileges in Maryland and Virginia where it is domiciled. Columbia First Federal Savings and Loan, having just completed a conversion from a mutual to a stock association, is in no position to take on National Permanent and its problems. And Meritor Savings Bank in Arlington has a substantial customer base and branch network in the District by virtue of its purchase of Capital City Federal last year.

The alternative, then, plays to the strength of a strategy that the chairman of New York's Chase Manhattan Corp. recently described as "opportunistic." Unquestionably, National Permanent, in its weakened condition, has become a target of opportunity for big banks outside the region. "It's a perfect entree" into the District for big out-of-state banks, declared the head of a local financial institution.

The perfect entree described by the official would give a money-center bank, for example, instant access to a fairly large customer base (nearly $1 billion in deposits) and an established branch network in a major consumer market. What's more, a financial heavyweight such as Chase or Citicorp could convert a savings bank in the District into a commercial bank with no strings attached. The recently approved D.C. interstate banking bill requires banks outside the region to agree to several strict investment standards before they can acquire a D.C. bank. But the measure has no provision covering thrifts, all of which are federally chartered in the District.

All that remains is for the FSLIC and a financial giant to agree on an acceptable price, possibly including cash assistance.