This page explains how Joseph D. Durbin (USATT# 1175696)'s rating went from 1218 to 1121 at the Butterfly Spin &Smash February Open held on 4 Feb 2023 - 5 Feb 2023. 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.