This page explains how Patrick Kin Luen Lui (USATT# 7924)'s rating went from 1919 to 1922 at the Butterfly MDTTC February Open held on - 15 Feb 2009. 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.