Why are there more men than women?

Worldwide, it is only about 2% more men, and this is skewed by the high ratios of China (+8%) and India (+7%). In these countries and others, the need for predominantly male workers (and mandated population control) has led in some cases to infanticide, as too many female babies could result in higher population growth, potentially overpopulation and famine.

In the US, the reverse is true (-3%), and one reason is that women are living longer than men, increasing the ratio of females in the elderly.

In the UK, the reverse is also true; more boys than girls are born, but by teenage the numbers have equalised (more mortality in the boys - the weaker sex) and thereafter there are more women than men.