This page explains how Bob Hall (USATT# 29955)'s rating went from 675 to 643 at the South Shore Sports & Butterfly Open held on 28 Oct 2017 - 29 Oct 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.