This page explains how Mauricio Vergara (USATT# 28649)'s rating went from 2154 to 2143 at the Westchester 2016 December Open held on 10 Dec 2016 - 11 Dec 2016. 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.