This page explains how David Guan (USATT# 217271)'s rating went from 1016 to 1009 at the HCTT Tuesday Night League event from 27 Feb 2018. 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.