The age when they started playing the Doctor to when they ended.
Of interest:
- Peter Davison was almost as young as Matt Smith when he started as the Doctor. And people complain of Smith’s age but not Davison’s. (Though maybe they did complain when Davison started 30 some odd years ago.)
- The actors of the classic Doctor Who start off older, get younger before going older again. I wonder if the same will hold true for the modern Doctor Who?
- Both Eccleston and McGann were only the Doctor for a very short time relative to the others. Though Eccleston was a much more successful incarnation of the Doctor than McGann. 😉