This page explains how Jacky Lau (USATT# 273296)'s rating went from 399 to 394 at the 2022 FREMONT BUTTERFLY DECEMBER OPEN held on 9 Dec 2022 - 11 Dec 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.