This page explains how Mark Brouda (USATT# 27868)'s rating went from 1231 to 1209 at the Quaker city Open held on - 30 Mar 2003. 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.