This page explains how Jim A. Engstrom (USATT# 70172)'s rating went from 1510 to 1506 at the South Shore Sports / Butterfly Open held on - 14 Nov 2010. 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.