This page explains how William Chan (USATT# 77422)'s rating went from 1797 to 1677 at the Boston TTC Div.B event from 18 Feb 2019. 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.