This page explains how Arseni Mouchinski (USATT# 1150994)'s rating went from 859 to 830 at the LYTTC Friday Pro League event from 21 Dec 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.