This page explains how Thierry Vilboux (USATT# 92059)'s rating went from 1292 to 1249 at the 2019 Butterfly WDCTT September Open held on 21 Sep 2019 - 22 Sep 2019. 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.