This page explains how Jason Lacey (USATT# 9257)'s rating went from 1558 to 1616 at the Portsmouth Open Invitational held on - 12 Sep 1999. 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.