SAN FRANCISCO (AP) - Nearly a million gays and lesbians identified themselves as members of same-sex couples in the 2000 census, which for the first time gives an authoritative record of homosexuals in America.

But the total gay population is much larger, since the census didn't provide an opportunity for single homosexuals to identify their sexual orientation, and didn't count gay couples who live apart.

That has some homosexuals fearing their calls for domestic partner rights and benefits such as marriage, health care and inheritance rights will get little attention.

"Why would politicians waste an hour on this if there are only 6,500 (male) couples in San Francisco, the queer capital of the world?" said Peter Altman, 42, who's been with his partner 11 years.

Census officials say the numbers are more accurate than those gathered in 1990, when the bureau assumed that all people who checked "spouse" or "married" to someone of the same sex had made a mistake. Such people were categorized either as heterosexual couples or other relationships such as roommates or relatives.

Still, the 2000 numbers cannot be used to estimate the nation's entire gay population, said Martin O'Connell, chief of the fertility and family statistics branch of the Census Bureau.

"It's hard to get a complete picture by only describing the living relationships of people living together," O'Connell said.

To date, the Census Bureau has reported that there are 479,107 same-sex couples sharing a household. This number will rise when data from all 50 states is released. The missing states are New Jersey, Texas, Pennsylvania, Tennessee, Virginia, Wisconsin, Mississippi and Arkansas.

According to the latest census statistics released Wednesday, California and Vermont lead the nation with the highest percentage of gay couples, while San Francisco has nearly twice as many same-sex partners as any other county.

There are 92,138 same-sex couples in California, including 8,902 in San Francisco. In Vermont, 1,933 same-sex couples responded to the census. Gay and lesbian couples make up nearly 1 percent of total households reported in both states.

The census found that gay couples represent 2.7 percent of San Francisco's households. However, San Francisco's total gay population is closer to 10 percent, or 80,000 people, according to San Francisco pollster David Binder.

"We're not talking about some sort of intangible concept of a gay family," said David Smith, spokesman for the Human Rights Campaign, a gay and lesbian advocacy group in Washington D.C. "We're talking about real people who live in a real assemblyperson's district."

The 1990 census counted 121,346 same-sex couples. These were people who checked "domestic partner" with someone of the same gender.

But O'Connell warned against comparing those numbers to last year's because of the way the forms were edited a decade ago. For example, two men identifying themselves as married could have been switched in 1990 to male and female and counted as a heterosexual couple, or listed as relatives or roommates instead of domestic partners.

The 2000 data did not reassign partners. Instead, it put everyone into the domestic partner category, and then classified the couples as homosexual or heterosexual. There are 3,850,524 heterosexual unmarried couples nationwide.

The same-sex numbers, while most likely undercounted, still show a lot about where the country's gay couples live and who they are.

The data shows there are more lesbian couples living in rural areas, while gay male couples tend to be in urban areas. California, Nevada, Florida and New York rank at the top for male couples, while Vermont, New Mexico, Oregon and Massachusetts have the most lesbian couples.

"Part of that might have to do with more of us having children than the guys. They still haven't caught up with us there," said Bobbi Cote-Whitacre, 53, of Grand Isle, Vt., who has been with her partner 34 years. "We tend to look for places that are safer or more of a rural country spot."