I scoured and searched the forums to look for documents that ranked Official Guide problems by difficulty (500-600, 600-700, 700-800 or similar). I was only able to find problems ranked or sorted by category/topics instead.

Also, I realize that the problems become harder and harder as the problem number ID increases, but it'd be useful to know where the cutoff is between 500-600 and 600-700 or 600-700 and 700-800. I also realize that ranking by difficulty is subjective, but such variance resulting from ranking by difficulty is acceptable by me too.

Does anyone have such a document? It'd be useful to help simulate practice tests by picking and choosing appropriate problems.

Thanks!