Baseball: What is an IP (Inning Pitched)?

A statistic in baseball used to determine how much a pitcher has pitched is record and called innings pitched. It is abbreviated by IP. This is the number of innings a pitcher has pitched and recorded outs. Because three outs consist of one inning, the IP statistic can be a fraction. In this case, the amount 50 1/3 will mean they pitched fifty total innings and an extra out. The amount of 50 2/3 will result in fifty innings pitched with an additional two outs. If a total is a whole number, they have pitched an even amount of innings. This can also be written as a decimal that is different than normal numbers. For example, 50.1 is the same as 50 1/3 innings, 50.2 is the same as 50 2/3, and 50.0 is the same as 50 innings.

Runners left on base are not counted in determining innings pitched. Only the outs that the pitcher has done will be counted for his own statistic. It is possible, however, for a pitcher to enter a game, give up several hits and runs, and leaves the game without recording an out and will be credited with zero innings pitched.

The amount of innings pitched has declined per decade due to the changes in pitching. Because of various changes, pitchers have been used differently and normally they have been used less in recent years. There are some changes in the NBA that have changed the way pitchers have been used. During the late 19^th century, pitchers threw from fifty feet away and exerted less stress on their arms. This allowed them to pitch more. Some pitchers also pitched underhand. In 1892, the pitching mound was moved back to sixty feet and this decreased the amount of innings pitched by almost 200 innings per pitcher. In the 1980's, a four-man rotation was created and bullpens were established more and more. This meant that less and less innings would be pitched per player. In today's standards, pitching 250 innings is a very rare occasion, while in the 1880's, pitchers would average over 600 innings per season.

Cy Young has pitched the most innings by far. His 7,354 2/3 innings pitched are considered one of the safest records in Major League Baseball. Second was Pud Galvin with just over 6,000 innings pitched. Walter Johnson is third with 5,914 2/3 innings. Fourth on the all time innings pitched list is Phil Niekro with just over 5,404 and fifth is Nolan Ryan with 5,386 innings.

Wikipedia, Innings Pitched