Convenience store sales on a same-store basis fell 1.3 pct year-on-year in June to 548.7 bln yen, the 11th consecutive month of decline, mainly due to a slump in sales of soft drinks, the Japan Franchise Association said The drop was also the 25th in the last 28 months The average purchase per customer fell 1.3 pct to 561 yen on a same-store basis, while the number of customers was unchanged at 964.1 mln, the association said. The total number of convenience stores as of June 30 stood at 39,269, up 2.6 pct from the previous year, it said On an all-store basis, sales rose 2.4 pct year-on-year to 600.6 bln yen while the average purchase per customer eased 1.0 pct to 561 yen, data from the association showed. The figures are based on data from the association's 11 member-companies, including Seven-Eleven Japan, Lawson Inc and FamilyMart Co Ltd