This page explains how David T Campbell (USATT# 59573)'s rating went from 1191 to 1183 at the Eldersburg Friday Night League event from 21 Oct 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.