This page explains how William R. Cooper (USATT# 5055)'s rating went from 1528 to 1518 at the 1999 4th Annual US Nationals W held on - 11 Dec 1999. 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.