This page explains how Houshang Bozorgzadeh (USATT# 4400)'s rating went from 1955 to 1939 at the US Nationals held on - 19 Dec 1999. 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.