Online retail sales growth will be measured for the first time, with a new indicator to be launched by the British Retail Consortium (BRC) and KPMG next week.
The BRC says the measure is a response to the "increasing significance" of online sales, and to requests from retailers to publish the figures.
Jonathan Reynolds, academic director of the University of Oxford's Institute of Retail Management, said, "There is a lot of hype about the growth in online sales. They are growing quickly but it is important to recognise that over nine pounds in every ten is still spent in traditional shops. As the range of ways people shop develops, an equally robust measure for non-store sales will be a valuable new piece of data."
The first batch of figures will be published on 11 November. It will show how much online, mail-order and telephone sales of non-food goods have grown compared with October 2007. The figures will cover non-store, non-food retail spending.