This page explains how Qi Guo (USATT# 80876)'s rating went from 1664 to 1646 at the NJTTC Monday League event from 13 Dec 2010. 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.