This page explains how Patrick Keville (USATT# 77971)'s rating went from 1920 to 1912 at the LYTTC Friday Pro League event from 30 Oct 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.