This page explains how Guenther Schroeder (USATT# 9813)'s rating went from 1638 to 1615 at the December Open held on - 22 Dec 2012. 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.