This page explains how Zaid Berrada (USATT# 86942)'s rating went from 1774 to 1754 at the Chicago Land Area Singles League event from 27 Dec 2011. 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.