This page explains how Olaf Surmann (USATT# 81607)'s rating went from 2143 to 2127 at the ICC JOOLA Fall Open held on 26 Aug 2023 - 27 Aug 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.