M&T Bank Corp. shares, which often seem immune to market swings, have fallen substantially in the past month.

Big moves-up or down-are not unusual for Buffalo-based M&T, because it is a thinly traded stock. Its movements don't always track the broader markets. But with shares now 14.1% off their high, some investors have taken notice.

The slide accelerated July 23 when, according to a recent Securities and Exchange Commission filing, chairman Robert G. Wilmers sold 79,000 of his share. The sale came six days after the stock peaked at $575.25.

Some speculated that Mr. Wilmers' sale suggested that he "knows when all good things must come to an end" and is reducing his position accordingly. But Kevin Timmons, an analyst at First Albany Corp., said Mr. Wilmers needed the cash to buy a vineyard. Mr. Wilmers was unavailable for comment.

Richard Lammert, the general counsel of M&T Bank, dismissed the notion that the sharp selloff was the result of investors' anxiety.

"If you look at the selloff in the company's shares and compare it to other banks, you'll find that it is proportional," said Mr. Lammert, who recently sold some of his M&T shares to fund his daughter's college tuition.

Mr. Timmons cited other possible reasons for a decline in M&T shares. The company's recent acquisition of Onbancorp produced a one-time charge, he said. And the economy in northern New York State where M&T operates is suffering side effects from a decline in the value of the Canadian dollar, Mr. Timmons added.

"What also could be impacting the stock is that the growth rate of loan production seems to be slowing," said Mr. Timmons. "However, all of these items are relatively minor."

In trading Wednesday banks again led the market in a selloff. The Standard & Poor's bank index fell 1.64%, while the Dow Jones industrial average fell 0.25%. The Nasdaq bank index was down 0.80%, and the S&P 500 lost 0.28%.

The biggest losers of the day included Citicorp $3.625, to $143.3125; BankAmerica Corp. $2.4375, to $81.8125; and NationsBank Corp. $2.0625, to $72.875.

PNC Bank Corp. shares were buoyed slightly by merger speculation in early morning trading, but sold off with the rest of the market as investors determined no deal was imminent. PNC closed up 18.75 cents, at $49.50.

Analysts continued to trumpet the strong fundamentals of banks, but pointed out that investors are still reluctant to enter the market because of uncertainty.

Troubles still continue to shake the Asian and Russian economies, while scandal rocks the White House.

The President's recent testimony did not necessary ease uncertainty in the market, said hedge fund manager Dale Jacobs.

"We have just as much uncertainty today as we did on Monday," said Mr. Jacobs. "Even though these banks stocks are cheaper, I want to see the whites of their eyes before I do aggressive investing."

Subscribe Now

Access to authoritative analysis and perspective and our data-driven report series.

14-Day Free Trial

No credit card required. Complete access to articles, breaking news and industry data.