U.S. retail sales dropped by the most in nearly two years in January, likely because of frigid temperatures and moderation following hefty gains in the past four months, suggesting a sharp slowdown in economic growth early in the first quarter.

With consumer spending making up two-thirds of economic activity in the U.S., the sales numbers indicate potentially weaker growth for the first quarter.

U.S. retail sales dropped sharply last month, in part because cold weather kept more Americans indoors, denting sales at car dealers and most other stores. Retail sales fell 0.9% in January from the previous month,