This page explains how Carl Plassmann (USATT# 82381)'s rating went from 906 to 843 at the Westchester 2015 December Open held on 27 Dec 2015 - 28 Dec 2015. 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.