This page explains how Zack Guido (USATT# 214914)'s rating went from 1717 to 1630 at the Westchester 2021 October 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.