The gene that causes color blindness is linked to the X chromosome and it is much more frequent in males than females because females have two X chromosomes. So for a female to suffer from color blindness, both of her X chromosomes should carry the genetic disorder.
In Economic theory, we learn that generally, the more older people there are, there is an increase in the demand of healthcare. As a result, the increase in demand for healthcare may increase prices and cause a higher demand for doctors and nurses.