 Ranking by bookseller sales figures continues today, although the process has remained proprietary.By the 1950s, "The Times"'s list had become the leading best-seller list for book professionals to monitor, along with that of "Publishers Weekly".In the 1960s and 1970s, shopping-mall chain bookstores B. Dalton, Crown Books, and Waldenbooks came to the forefront with a business model of selling newly published best-sellers with mass-market appeal.