This page explains how Yichi Zhang (USATT# 89328)'s rating went from 2550 to 2549 at the 2015 Butterfly Aurora Cup held on - 18 Jan 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.