This page explains how Mark Johnson (USATT# 26863)'s rating went from 1578 to 1572 at the SVTTC Sunday U2000 event from 15 Jan 2017. 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.