This page explains how Rex Edward Joy (USATT# 17580)'s rating went from 1309 to 1280 at the Westchester 2017 August Open held on 26 Aug 2017 - 27 Aug 2017. 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.