This page explains how Jean William Barthold (USATT# 71069)'s rating went from 1458 to 1559 at the Westford TTC 2019 December Open held on 8 Dec 2019 - 8 Dec 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.