This page explains how Mohamad Alzein (USATT# 215073)'s rating went from 1991 to 1987 at the 2021 Edgeball Chicago International Open held on 30 Oct 2021 - 31 Oct 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.