This page explains how Philip Zummo (USATT# 279590)'s rating went from 977 to 971 at the NTTC September 9th, 2023 league event from 9 Sep 2023. 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.