What percentage of men are bisexual and what are the measurements of different statistics available today and in past for US and world?

Sexuality occurs along a bell curve; the number of people who are 100% gay and 100% straight is relatively small, while the number of people who have the potential for bisexuality is relatively large. In general, everywhere in the world, at all times in human history, 6-10% of the population experiences attraction to people of the same sex.