1980 MLB Losses by Team

The Seattle Mariners led all of MLB in losses in 1980, with 103, 5 ahead of the Chicago Cubs. The average across 26 MLB teams is 80.8.

Led all of MLB in 1980 Seattle Mariners 163 games

103 Losses 5 clear of Chicago Cubs

#	Team	League	G	L
1	Seattle Mariners	AL	163	103
2	Chicago Cubs	NL	162	98
3	California Angels	AL	160	95
3	New York Mets	NL	162	95
3	Toronto Blue Jays	AL	162	95
6	Chicago White Sox	AL	162	90
7	San Diego Padres	NL	163	89
8	St. Louis Cardinals	NL	162	88
9	San Francisco Giants	NL	161	86
10	Texas Rangers	AL	163	85
11	Minnesota Twins	AL	161	84
12	Cleveland Indians	AL	160	81
	MLB average			80.8
13	Atlanta Braves	NL	161	80
14	Oakland Athletics	AL	162	79
14	Pittsburgh Pirates	NL	162	79
16	Detroit Tigers	AL	163	78
17	Boston Red Sox	AL	160	77
18	Milwaukee Brewers	AL	162	76
19	Cincinnati Reds	NL	163	73
20	Montreal Expos	NL	162	72
21	Los Angeles Dodgers	NL	163	71
21	Philadelphia Phillies	NL	162	71
23	Houston Astros	NL	163	70
24	Kansas City Royals	AL	162	65
25	Baltimore Orioles	AL	162	62
26	New York Yankees	AL	162	59

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.