This page explains how Mark Kasdorf (USATT# 26450)'s rating went from 810 to 773 at the Westford TTC September 2023 Open held on 3 Sep 2023 - 3 Sep 2023. 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.