Equibase Company, the Thoroughbred industry's official database for racing information, has incorporated two changes to its performance-based horse rating that takes into consideration the weight of accomplishment at the highest levels and early career recognition for maiden special weight winners with limited starts, the data gather said in a press release on Wednesday. The Equibase rating--which is intended to provide an unbiased performance score based on race outcomes and measurable factors such as speed, race strength, track conditions and trip factors--launched last fall with inaugural ratings races conducted at Santa...