MLB pitching staffs have changed dramatically from 1984-2014

The number of pitchers used by MLB teams per season has changed dramatically over the last 30+ years. Whereas you once could count on a team you left spring training to be your pitching staff for the year, nowadays not even close.

Specialists, injuries and lack of complete games have caused a incredible rise in relief pitchers appearances. In turn this has caused pitchers to burn out or be exposed as no good. This has lead to a meteoric rise pitchers.

Teams went from using 16 pitchers a year in 1984 to 25 pitchers in 2014. A 56% increase. Pitchers per game went from 5 in 1984 to 8 in 2014. A 60% increase.

This is why you see the William Cuevas, Noe Ramirez, etc. types pitching in meaningful games throughout the year.

It is also why the games last so long now.

Here are the numbers.  
 

YEAR	TOTAL	TOTAL PITCHING APPEARANCES	COMPLETE	PITCHES	AVG PITCHERS	AVG # OF PITCHERS
	GAMES	PER YEAR/PER TEAM	GAMES	PER GAME	PER GAME	PER TEAM/YEAR
1984	2,106	11,122	632	268	5	16
1999	2,430	17,242	237	292	7	21
2014	2,430	19,301	118	290	8	25