According to International Business Times:
Only 28% of heterosexuals believe that “there is no middle ground – you are either heterosexual or you are not”.
Kinsey estimated that around 10% of the population was gay, although this percentage was criticised by the American Statistical Association. However, a 2011 Gallup poll asked over 1,000 people in the US “what percentage of Americans today would you say are gay or lesbian?” On average, respondents guessed that 1-in-4 Americans were.