Describes a new baseball statistic called GPA (Gross Productivity Average). The GPA measures how many runs a batter creates for his team or how many runs a pitcher prevents the opposing team from scoring by comparing each player's production to that of the average major league player from 1997 to 2009. The GPA is reported on a scale similar to that used for batting average which makes it is easy to understand. Each player's GPA can be accurately adjusted to take into account his contributions on the base paths and the ballparks in which he played.