By the 1970s, Provincetown had a significant gay population, especially during the summer tourist season, when restaurants, bars and small shops serving the tourist trade were open. There had been a gay presence in Provincetown as early as the start of the 20th century as the artists' colony developed, along with experimental theatre. Drag queens could be seen in performance as early as the 1940s in Provincetown. In 1978 the Provincetown Business Guild (PBG) was formed to promote gay tourism. Today more than 200 businesses belong to the PBG, and Provincetown is perhaps the best-known gay summer resort on the East Coast. The 2010 US Census revealed Provincetown to have the highest rate of same-sex couples in the country, at 163.1 per 1000 couples.