U.S. magazine sales fell nearly 10 per cent in the first half of 2012, a troubling sign for print publishers that suggests Americans are still being careful about discretionary spending. The Audit Bureau of Circulations said overall circulation, including subscriptions, was just about flat. But single-copy sales, which are more closely watched -because publishers make more money from them- continued to fall. Subscriptions are typically sold at a discount. The industry group says single-copy sales at newsstands and other retailers totalled 26.4 million in the first six months of 2012.