This page explains how Brett Preston (USATT# 271503)'s rating went from 634 to 579 at the ICC JOOLA Fall Open held on 10 Sep 2022 - 11 Sep 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.