This page explains how Mark Johnson (USATT# 26863)'s rating went from 1244 to 1193 at the ICC JOOLA Winter Open 2021 held on 13 Nov 2021 - 14 Nov 2021. 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.