Kinsey scale

[Michiko]

The [Kinsey scale] attempts to measure sexual orientation, from 0 (exclusively heterosexual) to 6 (exclusively homosexual). It was first published in Sexual Behavior in the Human Male (1948) by [Alfred Kinsey], [Wardell] Pomeroy and others, and was also prominent in the complementary work Sexual Behavior in the Human Female (1953).
Heres the scale:
0 Exclusively heterosexual
1 Predominantly heterosexual, only incidentally homosexual
2 Predominantly heterosexual, but more than incidentally homosexual
3 Equally heterosexual and homosexual
4 Predominantly homosexual, but more than incidentally heterosexual
5 Predominantly homosexual, only incidentally heterosexual
6 Exclusively homosexual