WASHINGTON: Consumer spending in the United States in September posted the smallest gain in eight months, a sign that shoppers grew cautious at the end of the third quarter. The Commerce Department said on Friday spending rose 0.1 per cent, the weakest showing since spending fell in January. Income growth inched up 0.1 per cent, which was the smallest amount in four months. Wages and salaries were flat following two months of big gains. Consumer spending is closely watched because it accounts for 70 per cent of economic activity. The overall economy slowed sharply in the July-September quarter to an annual rate of 1.5 per cent, less than half the 3.9 per cent rate seen in the April-June period.