What is the fine-grained topic of the following text: consumers within the top 25-30 percentile in terms of the number of categories purchased online in the past 6 months) were once the largest driver of ecommerce growth (making up 41 per cent of Canada’s ecommerce users in 2014) this group has slowly shrunk in recent years. Only return the topic.
Ecommerce growth driven by top percentile online consumers in Canada