This page explains how Nancy Calderone (USATT# 98061)'s rating went from 823 to 810 at the 2019 South Shore Sports Butterfly Open held on 16 Nov 2019 - 17 Nov 2019. 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.