This page explains how Johnny H Wong (USATT# 17990)'s rating went from 1849 to 1817 at the 888 TTC $15K Butterfly / XIOM Labor Day Challenge held on 3 Sep 2021 - 6 Sep 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.