This page explains how Sean Masterson (USATT# 77070)'s rating went from 1679 to 1664 at the Tucson Open & Giant Round Robin Tournament held on 31 Oct 2015 - 1 Nov 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.