This page explains how Peter Lawless (USATT# 218487)'s rating went from 1553 to 1555 at the Boston TTC Div.B event from 13 Jan 2020. 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.