This page explains how Xiaozhou Zang (USATT# 15190)'s rating went from 1642 to 1645 at the 2010 Junior Olympics/Nationals held on - 2 Aug 2010. 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.