High unemployment has had some impact on the breakfast business at McDonald's Corp as fewer people pick up food on the way to work, Chief Executive Jim Skinner said on Tuesday.

The impact has been inconsistent, reflecting the uneven path of unemployment across the nation, Skinner told reporters after a Chief Executives Club of Boston lunch.

It depends on the market. In areas where you have extraordinary unemployment, and people are not up and about in the morning, you're going to have some fall-off, he said.

U.S. unemployment is flirting with 10 percent -- the highest level in roughly three decades -- and many investors have worried what impact that would have on McDonald's high-margin breakfast business that accounts for around 25 percent of U.S. sales.

According to many analysts, McDonald's breakfast sales exceed those at every other fast-food chain.

Shares of McDonald's were down 13 cents to $59.07 in afternoon trade on the New York Stock Exchange.

(Reporting by Ros Krasny and Ross Kerber in Boston and Lisa Baertlein in Los Angeles, editing by Dave Zimmerman)