Braudel and Reynold have made a systematic study of European market towns between the 13th and 15th century. Their investigation shows that in regional districts markets were held once or twice a week while daily markets were common in larger cities. Over time, permanent shops began opening daily and gradually supplanted the periodic markets, while peddlers or itinerant sellers continued to fill in any gaps in distribution. The physical market was characterised by transactional exchange and bartering systems were commonplace. Shops had higher overhead costs, but were able to offer regular trading hours and a relationship with customers and may have offered added value services, such as credit terms to reliable customers. The economy was characterised by local trading in which goods were traded across relatively short distances. Braudel reports that, in 1600, grain moved just ; cattle ; wool and woollen cloth . However, following the European age of discovery, goods were imported from afar – calico cloth from India, porcelain, silk and tea from China, spices from India and South-East Asia and tobacco, sugar, rum and coffee from the New World.