This page explains how Alan Tang (USATT# 81663)'s rating went from 2035 to 2009 at the Swan Friday O2000 Team League event from 23 Jan 2015. 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.