This page explains how Gary Osmanoff (USATT# 13305)'s rating went from 2190 to 2171 at the LYTTC Friday Pro League event from 15 Dec 2014. 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.