This page explains how Dahua Song (USATT# 223130)'s rating went from 1990 to 1993 at the LYTTC Friday Pro League event from 10 Aug 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.