Americans bought more cars, furniture and electronics in August, but held back spending on most other retail purchases. The Commerce Department says spending at retail businesses rose 0.2 per cent last month, the smallest gain in four months. Excluding volatile spending on cars, gas and building supplies, sales increased 0.2 per cent, less than half July’s 0.5 per cent gain. The modest retail sales figures suggest consumers may be growing more cautious about spending, which could sl