The agency says lower sales at motor vehicle and parts dealers were not entirely offset by gains in food and beverage stores.
Sales declined in four of 11 subsectors representing 41 per cent of retail trade.
The largest contributor to the decrease in dollar terms was a 1.9 per cent decline in sales at motor vehicle and parts dealers.
Sales rose at food and beverage stores, specialty food stores, electronics and appliance stores, general merchandise stores, department stores, building supply stores and garden stores.
Lower sales were recorded in seven provinces in October.
Also on HuffPost