(LOS ANGELES) -- An estimated nine million Americans -- or nearly four percent of the total population -- say they identify as lesbian, gay, bisexual or transgender, according to a new report released this week from the Williams Institute, a think tank devoted to LGBT research at UCLA.
Bisexuals make up slightly more than half that group -- 1.8 percent of the total U.S. population -- and they are substantially more likely to be women than men.
The report is the most up-to-date assessment of that population and produced a lower population percentage than the 10 percent number that advocacy groups have used in the past, which was based on Alfred Kinsey studies from 1948.
The new data comes on the heels of another recent report published by the Institute of Medicine for the National Institutes of Health emphasizing the need for more federally funded research on LGBT health problems.
"Sexual orientation is complex, but measurable," said Gary J. Gates, chief researcher and a Williams Distinguished Scholar. "Hopefully, this will begin to prompt some dialogue on what it means when we say LGBT."
Other key findings were that an estimated 19 million Americans, or 8.2 percent of the population, said they have engaged in same-sex behavior, and 25.6 million, or 11 percent, acknowledged some same-sex attraction.
Gay advocacy groups are hailing the report as a critical first step to inform public policy, research and federal funding. They say the information is crucial in identifying health and economic disparities, discrimination, domestic partnership benefits and the impact of same-sex marriage.
The report was based on a collection of previous surveys in the United States and around the world.
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