This page explains how Ruth Y Huang (USATT# 270016)'s rating went from 1290 to 1289 at the HITTA Weekly League event from 17 Sep 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.