Although illegal in China, some of the smaller massage parlors are sometimes linked to the sex industry and the government has taken a number of measures in recent times to curb this.In a nationwide crackdown known as the yellow sweep ("Yellow" in Mandarin Chinese refers to sexual activities or pornographic content), limitations on the design and operation of massage parlors have been placed, going so far as requiring identification from customers who visit massage establishments late at night and logging their visits with the local police.Prostitution in Nepal is illegal so the owners of such massage parlours do not explicitly solicit sex and the paying of police bribes is a customary part of the operation.[9] In 1996, foreign women made up the majority of prostitutes from forty sex establishments in eighteen border provinces that were actually brothels masquerading as karaoke bars, restaurants and traditional massage parlours.[10] In mid-1997, an increasing number of young girls, more than 60% of which were under 18 years old, were entering Thailand through the Mae Sai checkpoint into massage parlors, brothels, etc.The Federation of Thai Spa Associations (FTSPA) in 2016 urged authorities to clamp down on sexual services being offered at some massage parlours.The FTSPA maintains that influential figures have used legal loopholes to open "pretty spas" or massage parlours where tourists can buy sexual services.[25] An ongoing study of the prostitution business in New York City by the Sociology Department of Columbia University found that, between 1991 and 2010, the rise of the Internet and mobile phones “have enabled some sex workers to professionalize their trade”, with a shift from street walking to "indoor" markets (including massage parlors and escort agencies), a geographical change in the concentration of sex work, and the growth of a more expensive luxury market.[26] In January 2011, an investigation by Time Out New York found New York City massage parlors charging a "house fee" (which is usually paid, up front to the parlor's mama-san) of $60 to $100 per visit, with an extra tip for the sex workers (usually around $40) for a massage and a basic “happy ending” (or manual stimulation of the penis until orgasm).[28] As of 2005, more than forty Asian massage parlors (mostly Korean) operated as fronts for in-call brothels in Washington, D.C., and each earned an average of $1.2 million a year.More than 200 other massage parlors (that did not openly advertise and were operated largely out of private homes and apartments) serving mainly Latino clients made an average of at least $800,000 a year.