This page explains how Jim A. Engstrom (USATT# 70172)'s rating went from 1506 to 1504 at the South Shore Sports/Butterfly Open held on - 13 Nov 2011. 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.