This page explains how Jiufeng Zhao (USATT# 223669)'s rating went from 1880 to 1880 at the PTTC Saturday League event from 1 Sep 2018. 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.