@Coxspurplepippin that may be, but if Anne can manage over 300 in a year then logic dictates that the younger ones could do more than they are. Anne doesn't have extra hours in her day and her 'behind the scenes' stuff presumably has to be managed too.
I know Kate and William have children but really, they could make a bit more of an effort. It's long been a matter of record that they do less than everyone else.