This page explains how Shandra Qiu (USATT# 270886)'s rating went from 1307 to 1157 at the 2021 San Antonio Fall Open held on 24 Sep 2021 - 26 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.