This page explains how Timothy Allen Tonn (USATT# 43128)'s rating went from 1821 to 1819 at the Schaumburg November Open held on - 10 Nov 2007. 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.