This page explains how Bob O'Rourke (USATT# 73165)'s rating went from 860 to 852 at the QTTC May Open held on - 22 May 2011. 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.