Department store sales in July fell 11.7 percent from a year earlier on a same-store basis, logging the 17th straight month of decline, an industry body said.
The rate of decline was the largest for a July since 1965, the oldest comparable data available, according to the Japan Department Stores Association.
Sales totaled around ¥618.58 billion, the association said. The summer shopping season was sluggish owing to stalled personal consumption amid the recession.
The association said customer traffic dropped due to unseasonably cool and rainy weather, which also affected sales of swimsuits and other summer items.
Some department stores held their bargain sales campaigns for summer items in June, a month earlier than usual, which contributed to the slump because they ate into demand in July, according to the association.