Attached is a spreadsheet with tables for all sizes of Pathfinder bipeds and quadrupeds. It also includes custom calculation fields for any STR value. It should also serve as a great gaming utility for anyone who wants to look up encumbrance values. If you see any problems with it, let me know and I will correct them.
HoloGnome's Pathfinder Encumbrance Tables for Bipeds and Quadrupeds v1.0.0