This page explains how Helen Ni (USATT# 35001)'s rating went from 1499 to 1489 at the MDTTC Tuesday/Friday 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.