Why is the American League so bad?

As of May 6th, there are only 3 teams in the American League that are above .500: The New York Yankees, Tampa Bay Rays and the Athletics. And the Athletics are only 1 game above .500.

• With the increase in number of Interleague games, the National League is currently 20 games ahead of the American League, if there were a league versus league standings.
• Of the top 9 teams by record In the Majors, 7 of them are National League teams. Then there are 3 AL teams of the 4 tied for 10th.
• The leaders of the AL West are 1 game over .500 and the leader of the AL Central is one game under .500.

What is the basis for this disparity between the leagues?

Here are some comparative stats between the leagues:

League	Runs	OPS	ERA
AL	2383	.715	4.22
NL	2444	.714	4.13

So, a fair difference in runs, which might explain the record difference.

Now lets looks at splits in interleague games

League	Interleague Runs	Interleague OPS	Interleague ERA
AL	732	.695	4.27
NL	794	.721	4.02

As we can see, the difference in runs is directly reflected in the Interleague games. And there is a high disparity with OPS and ERA.

SO which teams have been doing the worst and best in Interleague play. Unsurprisingly, the Yankees top the list in winning percentage at 5-1. But then you have the Reds, Pirates, Diamondbacks, Rockies (!), Brewers, and Padres, at a combined 64-34. Among the 10 worst teams in Interleague Play, 8 are AL teams: the Rangers, White Sox, Orioles, Angels, Royals, Jays, Twins and Astros are 32-56. So even through the worst team of all in Interleague, the San Francisco Giants at 1-8, is from the NL, there is still a wide disparity between the leagues.

I’m guessing this disparity slows down or sees a reversal as we continue the season, but it has been a dominant start to the season for the National League.