This page explains how Thomas J. Huff (USATT# 6854)'s rating went from 1521 to 1519 at the Eldersburg Friday Night League event from 17 Dec 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.