"The national-level Youth2000 study reported a prevalence rate of 8.8% for non-heterosexual students, using a sexual identity question (Le Brun et al., 2005). The Dunedin Multidisciplinary Health and Development Study found that 24.5% of females and 10.7% of males of a Dunedin birth cohort reported any same-sex attraction by age 26 (Dickson et al., 2003). In comparison, the Christchurch Health and Development Study found that by age 25, 12.5% of a Christchurch birth cohort reported any same-sex attraction, any same-sex behaviour, or a lesbian, gay or bisexual identity (Fergusson et al., 2005)."
Source found here.
