WASHINGTON (AP) _ Low inflation, plentiful jobs and low interest rates combined to fuel a retail buying binge in 1998 that helped keep the American economy growing robustly in the face of foreign economic problems.

Retail goods _ particularly cars and building materials _ sold strongly during the crucial holiday shopping season, pushing sales up 0.9 percent to a seasonally adjusted $231 billion in December, the Commerce Department said today.

For the year, sales rose 5.1 percent to $2.7 trillion following a gain of 4.3 percent in 1997.

Automotive sales jumped 2.5 percent in December and, for the year, they were 5.7 percent higher, despite strikes that halted General Motors production in June and July.

Earlier this month, auto companies said they sold 15.6 million cars and light trucks last year, the most in 12 years.

Consumer spending _ which represents about two-thirds of economic activity _ kept the U.S. economy growing robustly in 1998, despite a plunge in export sales to Asian and other troubled economies that destroyed more than 200,000 jobs in manufacturing. Laid-off factory workers apparently found other jobs and the nation's unemployment rate last year, 4.5 percent, was the lowest in 29 years.

A side effect of the Asian crisis _ the lowest mortgage rates since the 1960s _ helped power record home sales. And that in turn propelled big gains in sales at furniture stores and hardware and building-supply centers.

Sales at building-supply and hardware stores rose 1.3 percent in December and 10.3 percent for the year. They rose 0.6 percent at furniture stores last month and 8.6 percent in 1998.