This page explains how Vasily Avram (USATT# 69750)'s rating went from 2015 to 1991 at the Boston TTC event from 24 Mar 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.