This page explains how Richard A. Dewitt (USATT# 47261)'s rating went from 2134 to 2121 at the Westchester 2017 November Open held on 18 Nov 2017 - 19 Nov 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.