This page explains how Dave Williams (USATT# 11140)'s rating went from 1662 to 1589 at the 1999 Potomac Spring Open held on - 23 May 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.