Baseball statistics

Baseball statistics collect a variety of metrics used to evaluate player and team performance in the sport of baseball.

Because the flow of a baseball game has natural breaks, and player performance is individually measurable, the sport lends itself to easy record-keeping and compiling statistics. Baseball "stats" have been recorded since the game's beginnings as a sport in the middle of the nineteenth century, and are widely available through the historical records of leagues such as the National Association of Professional Base Ball Players and the Negro leagues, although the consistency, standards, and calculations are often incomplete or questionable.

Since the National League (NL) was founded in 1876, statistics in the most elite levels of professional baseball have been kept, with efforts to standardize the stats and their compilation improving during the early 20th century. Such efforts have evolved together with advances in technology ever since. The NL was joined by the American League (AL) in 1903; together the two constitute modern Major League Baseball. A number of statistics are defined in the Official Baseball Rules, which task the official scorer with providing a report after each game.

Advances in both statistical analysis and technology made possible by the "PC revolution" of the 1980s and 1990s have driven teams and fans to evaluate players by an ever more elaborate set of statistics, which hold them to ever-evolving standards. With the advent of these methods, players can be compared across different eras and run scoring environments.