This page explains how George S. Aitken (USATT# 3797)'s rating went from 1521 to 1500 at the US Open held on - 6 Jul 2013. 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.