This page explains how Carlos I. I. Estrada (USATT# 39831)'s rating went from 1951 to 1979 at the Butterfly 2019 October BTTC Tournament held on 11 Oct 2019 - 13 Oct 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.