1990 MLB Earned Run Average by Team

The Oakland Athletics led all of MLB in earned run average in 1990, with 3.18, 0.19 ahead of the Montreal Expos. The average across 26 MLB teams is 3.86.

Led all of MLB in 1990 Oakland Athletics 162 games

3.18 Earned Run Average 0.19 clear of Montreal Expos

#	Team	League	G	ERA
1	Oakland Athletics	AL	162	3.18
2	Montreal Expos	NL	162	3.37
3	Cincinnati Reds	NL	162	3.39
4	Pittsburgh Pirates	NL	162	3.40
5	New York Mets	NL	162	3.42
6	Chicago White Sox	AL	162	3.61
7	Houston Astros	NL	162	3.62
8	San Diego Padres	NL	162	3.68
9	Boston Red Sox	AL	162	3.72
9	Seattle Mariners	AL	162	3.72
11	Los Angeles Dodgers	NL	162	3.74
12	California Angels	AL	162	3.81
13	Texas Rangers	AL	162	3.83
14	Toronto Blue Jays	AL	162	3.84
	MLB average			3.86
15	St. Louis Cardinals	NL	162	3.88
16	Kansas City Royals	AL	161	3.93
17	Baltimore Orioles	AL	161	4.07
18	San Francisco Giants	NL	162	4.08
19	Philadelphia Phillies	NL	162	4.09
20	Milwaukee Brewers	AL	162	4.11
21	Minnesota Twins	AL	162	4.14
22	New York Yankees	AL	162	4.23
23	Cleveland Indians	AL	162	4.27
24	Chicago Cubs	NL	162	4.34
25	Detroit Tigers	AL	162	4.39
26	Atlanta Braves	NL	162	4.58

A team's total is its players' numbers for the club added up, so a player traded mid-season counts for each team only what he did there. Rates such as ERA and batting average are worked out from the team's summed totals, not averaged across players.