Convenience stores represent 34.8% of all retail outlets in the United States with their ranks outnumbering drugstores, supermarkets and dollar stores combined. For the second year, Convenience Store News partnered with Nielsen’s TDLinx to find the top c-stores last year. TDLinx defines a convenience store as a store that includes a broad merchandising mix, extended hours of operation and a minimum of 500 SKUs. Once again, convenience giant 7-Eleven Inc. led the pack, adding a net 961 locations for a 14.4% increase in its U.S. store base. The other 19 are at the jump.