Statistics are the lifeblood of baseball. Managers pore over batting averages to determine game day lineups and batting orders; high runs batted in and low earned run averages earn praise from the press, higher salaries from the front office, and love from fans; and fantasy baseball players' fates rise and fall with each statistical change. The rise of the RC/27 and other more complex, formula-driven stats has made numbers even more important to understanding and appreciating the game. For all these baseball buffs and more, Frederick E. Taylor has a new measure of hitting prowess that just might be a game changer.Taylor's potential runs per game (PRG) measure accounts for batters getting on base, advancing runners, and driving in runs, and separates leadoff and second batters from those in the middle of the order. He introduces the measure, explains how it works, and applies it to players past and present. Taylor breaks the history of major league baseball into eight eras based on differences in runs scored per game. He systematically -- player-by-player and position-by-position -- compares the results of the PRG measure to those drawn from other statistics, such as on-base percentage and slugging average. Taylor shows that PRG is more accurate and that career clutch hitting is a myth.Sabermetricians, baseball fans of all stripes, and anyone who earns a living from the sport will find a wealth of information and a whole new stat to obsess over in The Runmakers. Measuring baseball will never be the same.