This page explains how Xiaozhou Zang (USATT# 15190)'s rating went from 1613 to 1638 at the 2008 JOOLA American Teams Ope held on - 30 Nov 2008. 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.