This page explains how Xuedong Chai (USATT# 267640)'s rating went from 114 to 91 at the Pong Planet Friday Night, Tuesday Night, And Saturday Leagues event from 11 Jan 2020. 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.