The schedule passed the first quarter point last week. So, seems like an appropriate time to compare this season to last, both what’s changed and what’s stayed the same. More after the jump.

In the analysis that follows, I’ll being comparing standings through last weekend’s series (May 21) to the same point in the schedule a year ago. Unless otherwise noted, statistical comparisons will be for the first 40 games of each season.

So, let’s get started in the AL.

AL East

Main change from a year ago is the Red Sox and Yankees swapping positions in the standings, while the other teams are in about the same place in the standings and the W-L column. As they’ve done for several years now, the Orioles are again outperforming their Pythag winning percentage while the Jays and Rays are undershooting that projection.

The biggest reason for the Yankees’ move up is, of course, their league-leading offense. How much better are they from last year?  Over their first 40 games, they’ve scored more than 50% more runs, 229 to 150, a massive difference. New York has just one regular older than 33 (Matt Holliday, who started 32 of the Yankees’ first 40 games). Only one Yankee team in the last 40 years (the 1994 club) has begun a season with fewer non-pitcher games started by players that old.

For the Red Sox, the change has been almost as great, but in the other direction, with their run production declining from 235 to 159, a 24% drop. Biggest change is the obvious one of Mitch Moreland taking David Ortiz‘s spot in the lineup, and batting like Mitch Moreland instead of like David Ortiz. The other regulars are mostly performing about as well as last year with the notable exception of Jackie Bradley Jr. whose OPS is down some 300 points compared to his hot start of a year ago. Forgotten man Pablo Sandoval has played only 17 games and is again on the DL after missing almost all of last season; he still has 3 years (including this season) and $57 million to go on his contract.

AL Central

In the Central, the Indians and Tigers are in about the same place for W-L record, but big changes for the other clubs, none more so than the Twins resurgence. Minnesota’s pitching has improved considerably, by almost three-quarters of a run, with a 4.21 ERA this year compared to 4.90 starting last season. Perhaps more important, though, is how they’ve fared in the clutch, with a team WPA over 5 for both pitching and hitting, compared to negative results a year ago. The total WPA change is +11.4, which is exactly how many more wins they have this year.

Chicago, which faded badly after a hot start a year ago, is understandably suffering a decline in their pitching results without Chris Sale anchoring the rotation. Overall ERA has ballooned by half a run (3.79, compared to 3.24) with a large chunk of that attributable to yielding over a third more home runs (48 to 35), many of those given up rookie Dylan Covey (7 starts, 7.64 ERA, 2.8 HR/9). Thrust to the top of the rotation, Jose Quintana has struggled, with a 2-5 record and 3.92 ERA, compared to 5-2, 1.54 a year ago.

Just two years removed from their world championship season (and with six starters from that club still in the fold), the Royals have struggled mightily to begin this season, scoring just 132 runs in their first 40 games, worst in the majors, and second worst in franchise history (ahead of only the 1981 club that was just one year removed from a World Series appearance).  That’s what happens when three of your regulars (Alcides Escobar, Alex Gordon, Eric Hosmer) have their OPS decline by almost 200 points from the year before.

AL West

In the West, Houston and Seattle have swapped top and bottom spots with the Angels improving by a few games and the other clubs about where they were last year. Astro pitching has struck out almost one-third more batters (400 to 303) than a year ago while the offense is sporting a .275 team BA after 40 games, the former the top result in the majors this season and the latter second only to the Nats at .278. Among all seasons, 400 strikeouts are second only to the 2013 Tigers (403), while .275 is the fourth best result in franchise history and highest outside of the 1996-2005 decade of uber offense.

For Seattle, their decline is all about pitching, with a team ERA (4.75) a run-and-a-half worse than a year ago (3.27). Last year, Seattle had 5 pitchers each make 8 starts in the team’s first 40 games; this year, it’s 9 pitchers making those 40 starts, with only two making 8 starts, and only one making multiple starts with an ERA under 4.00 (James Paxton, 1.43).

NL East

NL Central

Lots of change in the Central with the biggest swings coming from the Brewers and Cubs, seven wins better and worse, respectively. Milwaukee’s hitters are 70 points better in OPS and their pitchers two-thirds of a run improved in ERA. All of that OPS improvement is in slugging with 156 extra-base hits this season compared to just 115 last year. To borrow an analogy from the financial world, the arrival of Eric Thames has been the “black sheep” event that has catalyzed the Brewer offense this year. Out of the majors for four seasons, Thames has been a huge surprise with All-Star totals so far this season, though he has started to cool with just a .493 OPS over his last 7 games; we’ll see how he and NL pitchers adjust to each other as the season progresses. Looking at Thames’s Korean League stats, he turned in a 40/40/40 season (2B/HR/SB) in 2015, something only Alfonso Soriano (2006) has done in the majors. I tried to find other examples of a 30 year-old bursting onto the scene like Thames, but there really aren’t very many; his 86 major league games aged 25-29 are easily the fewest of any age 30 player starting 30 of his team’s first 40 games and posting 1.000 OPS, with Ken Williams (1920, 148 games) and Stephen Vogt (2015, 149 games) next on the list (looking at all major league service before age 30, Thames’s 181 games are the fourth fewest, behind Williams, Vogt and Dale Long).

For the Cubs, their main problem has been on the mound with their team ERA at 3.91 compared to 2.64 last year, and allowing 50 home runs compared to just 29 a year ago. All four of their returning starters are off their form of a year ago, especially at the top of the rotation with Jake Arrieta (5.44 ERA, was 1.29) and Jon Lester (3.57, was 1.88). And, Brett Anderson (8.18 ERA) replacing Jason Hammel (2.31) just hasn’t worked out. The Cubs’ defense also hasn’t helped them, allowing an unearned run in 19 of their first 40 games, the most in the majors this year.

NL West

Lots of movement in the standings out west with the Rockies and D-Backs making big strides forward and the Giants on the slide. For Arizona, their team batting stats are almost identical to last year’s marks, so their rise seems mostly attributable to better work on the mound with Zack Greinke (2.79 ERA, was 5.26) pitching more like Zack Greinke, and Taijuan Walker (3-3, 3.91) replacing Shelby Miller (1-4, 6.94).

The Rockies’ changes have been more dramatic, especially among their pitchers with just one returning starter (Tyler Chatwood) and three rookies (German Marquez, Kyle Freeland, Antonio Senzatela) and a second year man (Tyler Anderson) holding down the other rotation spots. Overall, the pitchers are about two-thirds of a run better than a year ago, with Freeland (4-2, 3.13) and Senzatela (6-1, 3.31) being particularly effective. On offense, starters have returned at every position (how unusual is that!)  and are producing very similar results to last year. Those changes don’t seem like they should have produced seven more wins than last year, an observation borne out by Colorado outperforming their Pythag by a very sizable margin.

For the Giants, the story is mainly the offense, with OPS down 100 points from a year ago, while the pitching has slid by half a run. San Francisco’s team OBP was only .289 to start the year, down 60 points from a year ago, and second worst in franchise history (since 1913), better than only the 100 loss 1985 club. The good news for the Giants so far is that they’ve significantly outperformed their Pythag; the bad news going forward is that they’ve significantly outperformed their Pythag.