This page explains how Willem Vandermeulen (USATT# 283319)'s rating went from 1279 to 1258 at the Mohawk Valley TTC League event from 17 Feb 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.