ROTFLMAO!
Define "true average score".
What good does it do to include scores I shot 27 months ago when I was still learning how to play WGT golf in my scoring average.
The USGA's handicap system uses only the 10 best scores from your most recent 20 rounds.
The PGA Tour uses each season's scores. In this weeks scoring average stats Charles Howell III 16th place position is based on 90 rounds while the #1 ranked player's scoring average (Sergio Garcia) is based on only 41 rounds.