This page explains how Harrison Ngo (USATT# 89471)'s rating went from 2071 to 1991 at the 2015 Decatur Open held on - 15 Aug 2015. 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.