Indeed, the numbers suggest that cuckolding, or at least thinking about it, is more common than you might imagine. For his forthcoming book, “Tell Me What You Want: The Science of Sexual Desire and How It Can Help Improve Your Sex Life,” Lehmiller surveyed thousands of Americans and found that 58% of men and about a third of women had fantasized about cuckolding.

https://www.cnn.com/2018/01/25/health/cuckolding-sex-kerner/index.html