[shoover]

That percentage has been and will be debated forever, even by proponents of the Browne PP model, but 4x25 has done well as recently as the past two decades.

Also the exact number is not all that critical. Earlier versions of Browne’s portfolio were more complicated and he simplified it to 4x25 later on, still allowing that people could tweak it if they must. But 4x25 is simple and works.