A drop in auto sales drove US retail sales lower in October after a strong gain in September, government data released Wednesday showed. Retail sales fell 0.3 percent, the Commerce Department reported, slightly more than analysts expected. The Commerce Department upwardly revised September\'s reading from an initial estimate of 1.1 percent to 1.3 percent, the largest increase since March 2010. Superstorm Sandy, which wreaked havoc on the East Coast in late October, had both positive and negative effects on sales, the department said. \"Some firms reported a drop in sales due to permanent or temporary store closures and stores having reduced business due to damage, fewer customer and/or lack of employees,\" it said. \"On the other hand, some firms reported sales increases due to significant sales of supplies for the affected areas and evacuees purchasing retail and food services in different geographic locales.\" Excluding automobile sales, which dropped 1.5 percent, retail and food services sales were unchanged from the prior month. On a 12-month basis, retail sales were up 3.8 percent in October. The retail sales data, which are not adjusted for price changes, are a key indicator of consumer spending that accounts for about 70 percent of economic activity.