The United States has approximately four million homosexual adults, representing about 1.7 percent of the population, according to a new study from a University of California, Los Angeles, research group.

The figure was compiled by demographer Gary Gates of the Williams Institute on Sexual Orientation Law and Public Policy, and based on five studies that asked participants about their sexual orientation.

Accurately counting the number of gays is fraught with difficulty under the best of circumstances. Sexuality is inherently fluid and ambiguous: Who do we count as gay? Anyone who regularly has sex with someone of the same gender? Anyone who has ever had any sexual contact with the same gender? Only those who self-identify as gay? Bisexuals?

Because sexual activity is typically private, surveys must rely on self-reports. Given the social stigma in some quarters surrounding homosexuality, many people may not want to admit to same-sex contact. Anonymous surveys can help get around this problem, but pose their own difficulties.

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Estimates from the 1930s and 1940s found a much higher incidence of homosexuality. In his book Damned Lies and Statistics, Joel Best, professor and chair of sociology and criminal justice at the University of Delaware, noted that Alfred Kinsey’s early studies found that approximately 10 percent of the males were more or less exclusively homosexual.

However, Best notes: “Later surveys, based on more representative samples, have concluded that the one-in-10 estimate exaggerated the amount of homosexuality. Typically, they find the 3 to 6 percent of males (and a lower percentage of females) have had significant homosexual experience at some point… and that the incidence of homosexuality among adults is lower — between 1 and 3 percent.”

Thus Gates’ new estimate is in line with most modern research — in fact, right between the lower and higher estimates.

The number of gays is a politically charged issue. Activists on all sides of the political spectrum have both exaggerated and downplayed the number of gays in America, according to their agendas. By any measure homosexuals are in the minority, and like any minority they don’t want their concerns to be ignored by the majority.

Of course, if gay rights is seen as a human rights issue, it does not matter whether there are four gays in America, or 400 million. The Constitution applies to everyone.