This page explains how Rachel Ou (USATT# 96726)'s rating went from 2020 to 2009 at the Topspin Advanced League event from 15 Dec 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.