This page explains how Vivian Cai (USATT# 1164293)'s rating went from 821 to 816 at the HCTT Players Development League event from 8 Jun 2019. 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.