This page explains how Ying Zhang (USATT# 90711)'s rating went from 1241 to 1251 at the Westchester 2015 May Open held on - 31 May 2015. 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.