How many relationships have a big age gap?
According to ABC News “across Western countries, about 8 per cent of all married heterosexual couples can be classified as having a large age gap (10 years or more). These generally involve older men partnered with younger women. About 1 per cent of age-gap couples involve an older woman partnered with a younger man.
The limited evidence on same-sex couples, however, suggests the prevalence rates are higher. About 25 per cent of male-male unions and 15 per cent of female-female unions demonstrate a large age gap.”