This page explains how Leo Yih (USATT# 262861)'s rating went from 407 to 421 at the Westchester December 2022 Open held on 29 Dec 2022 - 30 Dec 2022. 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.