This page explains how Thelma Tybie Sommer (USATT# 10155)'s rating went from 1138 to 1136 at the 2004 USA Nationals Championshi held on - 18 Dec 2004. 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.