This page explains how Dahua Song (USATT# 223130)'s rating went from 1786 to 1809 at the Barry Dattel Memorial Open held on 18 Jan 2020 - 18 Jan 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.