This page explains how Raymond F. Chen (USATT# 4809)'s rating went from 1642 to 1627 at the Potomac Millennium Open held on - 19 Nov 2000. 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.