the dissemination of accurate information about the swinging lifestyle. Subgroups Bisexuality and same-sex activity Attitudes to same-sex activity and bisexuality vary by culture and locale, and by gender. Female bisexuality and bicuriosity are common in swinging and tend to be the norm among participants; Similarly, the online swinger site Swinger Social Network demonstrates that their female membership approximates a 50% population of bisexual females. By contrast, male same-sex activity is usually, though not always, unwelcome. One source, covering "Chicago's first and only all bisexual [club]," stated that in the founders' view "The [swinging] lifestyle is pretty homophobic" and "male bisexuality was erased", although an "underground market" existed. Swing clubs and other facilities exist for gay and bisexual interests in both genders, but differ – for example bathhouses for gay men, many of which were forced to close because of concerns over AIDS transmission, whereas women's clubs are "comparatively rare" and tend to be organized as private events, or niche clubs with high popularity for their events. Selective swinging Most swingers' clubs do not bar entrance into their facilities based on race, national origin, physical appearance or age. The average swinger is married, professional, middle-class and in their 40s. However, younger swingers seeking peer group options find this is not always possible at conventional swingers' clubs because of normal demographics. Similarly, those individuals who seek to specifically exclude others they personally view as unattractive are often disappointed at many swingers' clubs because the patrons are not screened to their standards. This desire by some has given rise to exclusive parties and clubs that exclude people based on looks or impose an upper age limit. 'Selective swinging' or 'urban swinging' events include mostly childless, unmarried young graduates whose average ages are as low as the late 20s, a group sometimes derided as "Ken and Barbie in the lifestyle" because of the emphasis on youth and physical attractiveness. Selective parties are often derided by other swingers as "exclusive" or "elitist" and contrary to the open and accepting nature that they feel swinging should be about. By region United States There are hundreds of sex clubs in the United States, ranging from ongoing house parties and meet-up groups to fully licensed businesses. It is estimated that there are over 3,000 swingers lifestyle clubs in North America. Since there is no relevant federal legislation, the legal requirements and legality of such establishments varies from state