This page explains how Ethan Du (USATT# 88599)'s rating went from 2200 to 2090 at the Spttc Saturday Night League event from 9 Dec 2017. 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.