This page explains how Ronald Cassidy (USATT# 30857)'s rating went from 1291 to 1318 at the Windy City Open held on - 9 May 2009. 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.