This page explains how Olivier Mader (USATT# 20734)'s rating went from 2018 to 2027 at the Butterfly 2020 February BTTC Tournament held on 21 Feb 2020 - 23 Feb 2020. 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.