This page explains how Barry K. K. Or (USATT# 29304)'s rating went from 1815 to 1787 at the ICC - Advanced League event from 21 Nov 2020. 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.