This page explains how Jerry Zhang (USATT# 223480)'s rating went from 2028 to 2021 at the 2022 HITTA Butterfly Fall Open held on 5 Aug 2022 - 6 Aug 2022. 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.