While margin widened slightly, analysts said they were concerned that it came at the expense of sales. Best Buy Co. shares tumbled more than 15% Tuesday, their biggest decline in more than eight years, after the retailer reported an unexpected decline in fiscal third-quarter profit and cut its outlook. "There's interest there from consumers on the latest and greatest, but really they are making trade-offs in their discretionary spending, not only across CE [consumer electronics], but within CE categories, where there are periods of time we may have historically seen them buy multiple large products in a year, they are being more choosey at this point in time," said Muehlbauer [Best Buy's CFO] on a conference call with analysts.