This page explains how Alex Kotlyar (USATT# 21222)'s rating went from 1643 to 1621 at the SpinBlock Monday Night League event from 22 Nov 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.