Retail sales nationwide advanced a solid 0.6 percent in January on the strength of booming business in general merchandise, food and hardware goods, the government reported Tuesday. The Commerce Department revised retail sales for December, however, to a monthly decline of 0.1 percent after reporting an increase of 0.2 percent originally last month. The 0.6 percent hike for January was the strongest since a 1.3 percent jump in November, the department's Census Bureau said. Excluding the auto business, a negative factor last month, sales were up a full 1 percent during January. All figures were adjusted for seasonal variations.