Hitters still peak in their mid-20s, but they decline faster after 30. By 34 the typical hitter is 60 points of wOBA off his peak, against 44 in the 2000s.
Roster Memo research · Updated November 6, 2026 · Every number on this page is computed from the data on each refresh
Aging curves show how much a typical hitter gains or loses from one season to the next at each age. We built them the standard way, from players who batted at least 100 times in back-to-back seasons (8,051 pairs), and compared two eras.
In both eras the curve is nearly flat from about 23 to 26, so hitters are at or near their best through their mid-20s. The difference is in the 30s.
At 30 the eras are close: the typical hitter was 21 points of wOBA below his peak in 2012 to 2024 and 18 in 2000 to 2011. By 34 the gap is 60 points against 44. Hitters now fall off faster in their 30s than they did in the 2000s.
For roster planning, the risk sits in the back half of long contracts: the same deal through a hitter's mid-30s now covers a steeper decline than it did 15 years ago.
The Evidence
wOBA by age, relative to peak
Points of wOBA below each era's peak. Built from back-to-back seasons.
2000 to 2011
2012 to 2024
Age
2000 to 2011
2012 to 2024
36
−60.2
−88.6
35
−50.1
−66.5
34
−44.0
−60.0
33
−36.1
−50.7
32
−31.4
−41.9
31
−25.3
−32.6
30
−18.1
−20.5
29
−11.2
−15.6
28
−8.0
−11.8
27
−6.2
−5.2
26
−1.1
−1.4
25
0.0
−0.2
24
−3.6
−2.1
23
−3.5
−2.4
22
−8.0
0.0
21
−17.4
−10.2
Source: Roster Memo analysis of Retrosheet data
Year-over-year change by age
Average change in wOBA from one season to the next, in points, with the number of player pairs.
From age
2000 to 2011
2012 to 2024
Pairs, 2000 to 2011
Pairs, 2012 to 2024
21 to 22
+9.4
+10.2
53
46
22 to 23
+4.5
-2.4
88
120
23 to 24
-0.1
+0.3
169
221
24 to 25
+3.6
+1.9
273
319
25 to 26
-1.1
-1.3
342
377
26 to 27
-5.1
-3.8
386
409
27 to 28
-1.8
-6.6
385
395
28 to 29
-3.2
-3.8
374
360
29 to 30
-6.9
-4.9
356
329
30 to 31
-7.2
-12.0
349
297
31 to 32
-6.0
-9.4
316
282
32 to 33
-4.8
-8.8
274
225
33 to 34
-7.8
-9.3
228
160
34 to 35
-6.2
-6.5
180
109
35 to 36
-10.1
-22.1
145
71
Source: Roster Memo analysis of Retrosheet data
How We Did It
This is the delta method: for each player with 100+ plate appearances in two straight seasons, take the change in his wOBA relative to the league that year.
Changes are averaged by age, weighted by the harmonic mean of the two seasons' plate appearances, then chained into a curve.
Ages with fewer than 40 pairs are left out. Age is as of June 30.
What This Can't Tell You
Only players good enough to keep playing are in the sample. Those who decline most often lose their jobs and drop out, so real declines are somewhat steeper than shown.
The earlier era overlaps the end of baseball's steroid years, which may have flattened its decline.
Sources: Retrosheet. The information used here was obtained free of charge from and is copyrighted by Retrosheet. Interested parties may contact Retrosheet at "www.retrosheet.org".