This page explains how Robert D. Halladay (USATT# 6380)'s rating went from 1275 to 1273 at the City Limits League event from 13 Dec 2003. 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.