This page explains how William Y. Y. Wong (USATT# 11251)'s rating went from 1591 to 1555 at the San Francisco Summer Open held on - 15 Aug 2004. 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.