Not that I care about this stuff you understand

[babysimon]

I predict that the 20th Doctor will be underage, and the 27th Doctor will be a newborn baby.

Caveats:

1) I calculated age by (year first appeared) - (year born) which is incredibly lazy and wrong.
2) Linear regression may not be the best approach, the correlation looks mediocre. But it was easy to do in OpenOffice and I'm lazy (see #1).
3) Paul McGann doesn't count.