This page explains how Keith Hemann (USATT# 220831)'s rating went from 1642 to 1607 at the 2023 HITTA Butterfly Spring Tournament held on 18 Mar 2023 - 19 Mar 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.