[ccp4bb] Proportion of MR in the PDB

[Nicholas keep]

Does anyone have a good estimate of the proportion of molecular 
replacement structures in the PDB?
I tried using the search tools at RCSB and PDBe.  The PDBe gives 55.1% 
but apparently only 3411 structures have phase determination information 
recorded, so this does not look to be terribly comprehensive.
Thanks
Nick Keep