This page explains how Krisna Chongsiriwatana (USATT# 91500)'s rating went from 1229 to 1159 at the 2014 US National Championships held on - 20 Dec 2014. 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.