So much for the Harry Potter phenomenon. The Guardian reports that tail sales grew at their slowest pace since November last month, according to the British Retail Consortium. While Harry Potter flew to the rescue of booksellers, other retailers were hit by a combination of rising interest rates and poor weather due to torrential flooding in the south of England. The BRC said sales rose 3.1% from a year earlier, down from 5.1% in June and the weakest figure for eight months. The like-for-like figure, which strips out extra floor space added by shops, rose only 1.2%, also the worst since November.