This page explains how Billie McCoy (USATT# 8794)'s rating went from 1159 to 1151 at the Huntsman World Senior Games held on - 7 Oct 2005. 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.