As a self-confessed statistics nerd, I figured this out. I just bought the 2011 US Almanac, which said 2.3 percent of men in the US identify themselves as gay. Estimating about 115 million adult males in the US, that means there are approximately 2,600,000 men in the United States openly identify themselves as gay. This does not include bisexual men and of course there are probably just as many men who are gay but will not admit it.
The statistics for lesbians is smaller. Only 1.3 percent of women identify themselves as lesbian. This means about 1,500,000 openly lesbian women in the United States. Again, this does not include bisexual women and does not consider those who are still in the closet.
1.8 percent of men identify themselves as bisexual, making that number about 2,070,000. 2.8 percent of women identify themselves as bisexual, making that number about 3,220,000 bisexual women in the United States.
2,600,000 gay men
2,070,000 bisexual men
1,500,000 lesbian women
3,220,000 bisexual women
9,390,000 total United States LGB population
This 9.39 million figure does not include anyone under 18. If you included the openly gay teenagers in America, the number would probably be well over 10 million. This means 3.8% of the adult population are openly gay, lesbian or bisexual. How large would this number be if everyone was completely honest about their sexuality?