This page explains how Robert Simmons (USATT# 5034)'s rating went from 1581 to 1539 at the 2004 Gateway Open held on - 19 Sep 2004. 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.