This page explains how Sophia Zhuo-yao Chen (USATT# 221729)'s rating went from 321 to 306 at the WCTTA Saturday League event from 13 Apr 2019. 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.