This page explains how Jiaying Mao (USATT# 275969)'s rating went from 91 to 63 at the ICC - Sunday Beginners League event from 18 Jun 2023. 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.