This page explains how Hau Lam (USATT# 37020)'s rating went from 1947 to 1900 at the OCTTA BUTTERFLY FIRST ANNUAL SENIORS OPEN held on 7 Oct 2022 - 9 Oct 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.