This page explains how Qi Cai (USATT# 223588)'s rating went from 1572 to 1561 at the Spttc Wednesday night league event from 8 Jan 2020. 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.