This page explains how Cosmo Pinkerton (USATT# 218068)'s rating went from 1189 to 1129 at the ICC - Sunday Beginners League event from 29 Apr 2018. 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.