This page explains how Isabella W. Zai (USATT# 1157628)'s rating went from 1223 to 1323 at the 2021 US National TT Championships Massachusetts State Qualifier held on 27 Mar 2021 - 28 Mar 2021. 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.