Most studies I've seen show self reports around 1-4% of the population report as being homosexual. Is this true?
From the answer below: Sexual Orientation and Health Among U.S. Adults, 2013
I would argue that, yes, the range seems correct. The relative Wikipedia article mentions more than thirty different surveys, and they seem to be in that range.
Some cities have up to 1/8th of homosexual population, for example Atlanta has an estimated 12.8% of homosexuals:
Self reporting as an homo- or bisexual excludes a number of people from the statistics. There are people that had non-heterosexual encounters or relationships only once, or only in the past and consider themselves heterosexual.
Among adults who identify as lesbian, gay, or bisexual, bisexuals comprise a slight majority (1.8% compared to 1.7% who identify as lesbian or gay); women are substantially more likely than men to identify as bisexual; estimates of those who report any lifetime same-sex sexual behavior and any same-sex sexual attraction are substantially higher than estimates of those who identify as lesbian, gay, or bisexual. There are also nearly 700,000 transgender individuals in the US. An estimated 19 million Americans (8.2%) report that they have engaged in same-sex sexual behavior and nearly 25.6 million Americans (11%) acknowledge at least some same-sex sexual attraction.
There are many degrees of sexual orientation between fully heterosexual and fully homosexual, deciding where the "line" is drawn is subjective (e.g. see the dated Kinsey scale). Some people identify as asexual and it's not clear how they should be considered.
Modern sexologists define gender identity along three different scales, sexual orientation being only one of them (two others being biological sex and gender identity), so the question "are you homosexual?" is quickly becoming meaningless by itself.
Each of us has a biological sex — whether we are female, male, or intersex. Our gender is our social and legal status as men or women. And sexual orientation is the term used to describe whether a person feels sexual desire for people of the other gender, same gender, or both genders.
Each of us has a gender and gender identity. Our gender identity is our deepest feelings about our gender. We express our gender identity in the way that we act masculine, feminine, neither, or both. Some of us are transgender — which means that our biological sex and our gender identity do not match up.
Each of us also has a sexual orientation. You may be bisexual, gay, lesbian or straight. Or you may be “questioning” — unsure about your sexual orientation.
According to Sexual Orientation and Health Among U.S. Adults, 2013:
Based on the 2013 NHIS data, 96.6% of adults identified as straight, 1.6% identified as gay or lesbian, and 0.7% identified as bisexual. The remaining 1.1% of adults identified as ‘‘something else,’’ stated ‘‘I don’t know the answer,’’ or refused to provide an answer