How we did it: On-course income for 2013 includes all money earned on the PGA Tour and the five international tours (Japan PGA, PGA European, Australasian, Southern Africa, Asian) and the Champions Tour, LPGA Tour, Ladies European Tour and the Japan LPGA through Dec. 1. It includes unofficial money won in non-tour events.
Off-course Income includes estimates of all money earned from endorsements, bonuses, appearance fees, corporate outings, speaking engagements, licensing fees (video games, trading cards, etc.), course architecture, books, instructional videos and businesses that capitalize on a person's status as a player, such as product lines including clothing, wine and turfgrass.
Investment income is not included.