the commonest pronunciation of the digraph th

In a previous blog I chose to arrange the distribution of /θ/ and /ð/ according to the position of the digraph - initial, medial and final positions.

Probability is another one which may prove useful if one doesn't know how to pronounce the digraph and needs to take a shot in the dark. Blog commentator jwl has made some very valuable remarks here. I'd like to combine position and probability:

1. isolated: commonest pronunciation is /θ/;
2. word-initially: /θ/ is commonest;
3. word-medially: /ð/ is commonest; 
4. word-finally: commonest is /θ/.