This page explains how Sean Koster (USATT# 212045)'s rating went from 1787 to 1752 at the 2023 Best of the West Open & Giant Round Robin held on 25 Feb 2023 - 26 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.