This page explains how Rafi Hosein (USATT# 17893)'s rating went from 1816 to 1815 at the LYTTC Friday Pro League event from 19 Feb 2021. 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.