Baseball Career Length in the Twentieth-Century: The Effects of Age, Performance, and Era

Richard G. Rogers, University of Colorado at Boulder
Jarron M. Saint Onge, University of Colorado at Boulder
William Witnauer, University of Colorado at Boulder

Although baseball is considered “the” American pastime, little is known about the career prospects of the individuals who play the game. This study fills that void by examining the careers of baseball players over the last century. Between 1902 and 1985, 5,767 position players started their careers and played 28,790 person years of Major League baseball. The average position player can expect to play just five years; over one in four position players will have only a single-year career, and at every point of a player’s career, the chance of exiting is at least 11%. Position players who start younger, perform better, and begin their career in more recent decades all have longer and more stable careers; nevertheless, baseball careers are not compressed versions of normal careers, but are substantially skewed toward early exit.