This page explains how Tom Ruan (USATT# 14167)'s rating went from 2009 to 1979 at the 2024 Meiklejohn North American Seniors Open held on 30 May 2024 - 2 Jun 2024. The links below take you to pages that describe various aspects of the rating processor.

The rating processor goes through 4 passes in order. The links take you to pages that provide detailed explanations of the calculations during each of the 4 passes.