This page explains how John C. Fredrickson (USATT# 5901)'s rating went from 1590 to 1571 at the TCTTA Friday League event from 22 Feb 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.