This page explains how Frank Kraehe (USATT# 1172817)'s rating went from 1399 to 1364 at the 2023 Butterfly September Tournament held on 10 Sep 2023 - 10 Sep 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.