Good Years and Flat Tires

July 28, 2018
                                                       Good Years and Flat Tires

 

              This is just a fun little thing I did when I was supposed to be working.   I was looking for the largest improvements and largest declines at each age.   To figure the gain or loss, I used the OPS in Year 2 minus the OPS in Year 1, multiplied by the Plate Appearances in whichever season had fewer Plate Appearances.  Eddie Mathews, for example, had a .767 OPS in 1952 and a 1.033 OPS in 1953, so that’s a gain of .266, or 266 points.   Mathews had 593 plate appearances in 1952 and 681 plate appearances in 1953, so we use the smaller number, 593, and multiply that by .266, and conclude that Mathews had an improvement as a hitter in 1953 of 158 bases.  That’s a very large improvement—the largest improvement for any 21-year-old in baseball history.   We’ll consider each integer to be a base, although, since we are multiplying based on OPS, that isn’t always exactly what it is, but that’s the easiest way to describe it. 

              I didn’t figure improvements or declines for 19th century players because (a) I don’t consider 19th century baseball to be major league baseball, and (b) with the constant rules changes in 19th century baseball players have enormous year-to-year performance changes, so they tend to disproportionately populate the lists.   Anyway, with that intro, here’s a summary by age:

 

Age 19

              38 players improved, 30 declined, 57% improvement.

 

Age 20

              118 players improved, 66 declined, 64% improvement.   The 64% is by far the highest improvement percentage for any age.

              The largest improvement was by Al Kaline, 1955.  Kaline improved by 169 bases relative to 1954. 

 

Age 21

              273 players improved, 222 declined, 55% improvement.

              The largest improvements were by Eddie Mathews, 1953 (158 bases) and Cesar Cedeno, 1972 (144 bases.)   The largest decline was by Alex Rodriguez, 1997; A-Rod lost 127 bases. 

Age 22

              615 players improved, 457 declined, 57% improvement.

              Five players improved by 100 or more bases at age 22, who were:

 

Ted

Williams

1941

22

152

Bryce

Harper

2015

22

135

Wayne

Garrett

1970

22

115

Joe

DiMaggio

1937

22

105

Boog

Powell

1964

22

104

 

              Two players declined by 100 or more bases at age 22:  Hal Trosky, 1935 (134 bases) and Ron Santo, 1962 (119 bases). 

 

Age 23

              976 players improved, 835 declined.  54% improvement.   Fifteen players improved by 100 or more bases at age 23, led by Woody English and including Hal Trosky and Ron Santo, who both recovered from their miserable aged-22 seasons.  I’ll just list the top ten, which cuts off Santo, who would be 11th on the list with +109:

Woody

English

1930

23

175

Hal

Trosky

1936

23

158

Reggie

Jackson

1969

23

153

Al

Simmons

1925

23

153

Troy

Glaus

2000

23

143

Jose

Canseco

1988

23

124

Denis

Menke

1964

23

123

Prince

Fielder

2007

23

118

Lloyd

Moseby

1983

23

113

Ruben

Sierra

1989

23

110

 

 

 

 

 

              Santo, after gaining 109 bases in 1963 as opposed to 1962, then picked up another 97 bases in 1964, almost making the "improvement list" in back to back seasons. 

              Eight players lost 100 or more bases at age 23, led by Bryce Harper (185 bases). 

 

Dave

Roberts

1974

23

-102

Jimmy

Williams

1900

23

-108

Bernie

Carbo

1971

23

-121

Boog

Powell

1965

23

-127

Jimmy

Sheckard

1902

23

-127

Johnny

Bench

1971

23

-128

Pablo

Sandoval

2010

23

-130

Bryce

Harper

2016

23

-185

 

 

Age 24

              1,481 players improved, 1,283 declined, 54% improvement.

              Twenty-two players have improved by 100 or more bases at age 24, led by Lou Gehrig in 1927: 

 

Lou

Gehrig

1927

24

188

Ralph

Kiner

1947

24

162

Jimmie

Foxx

1932

24

161

Ryne

Sandberg

1984

24

154

John

Olerud

1993

24

133

Richard

Hidalgo

2000

24

125

Fernando

Tatis

1999

24

123

Ernie

Banks

1955

24

122

Johnny

Bench

1972

24

121

Chili

Davis

1984

24

119

 

              Gehrig’s improvement in 1927 is the largest season-to-season improvement in major league history, if measured by this approach. 

              Eleven played lost 100 or more bases at age 24, led by George Scott in his epically awful 1968 campaign:

 

Woody

English

1931

24

-100

Mark

McGwire

1988

24

-100

Jhonny

Peralta

2006

24

-101

Augie

Galan

1936

24

-102

Reggie

Jackson

1970

24

-103

Arky

Vaughan

1936

24

-105

Sam

Crawford

1904

24

-111

Jeff

Burroughs

1975

24

-117

Aramis

Ramirez

2002

24

-125

Mel

Ott

1933

24

-126

George

Scott

1968

24

-142

 

Age 25

              1,871 players improved, 1,662 declined, 53% improvement.

              Twenty-five players improved by 100 or more bases at age 25, led by Adrian Beltre in his 48-homer season in 2004.   More players had 100-base improvements at age 25 than at any other age. 

 

Adrian

Beltre

2004

25

184

Al

Cowens

1977

25

152

Sal

Bando

1969

25

146

Babe

Ruth

1920

25

144

Kirby

Puckett

1986

25

136

Rusty

Staub

1969

25

129

Sherry

Magee

1910

25

129

Bobby

Higginson

1996

25

127

Bobby

Murcer

1971

25

126

George (1B)

Burns

1918

25

122

 

              Only six players lost 100 or more bases at age 25: 

 

Rocky

Colavito

1959

25

-101

Boog

Powell

1967

25

-102

Heinie

Manush

1927

25

-106

Adam

Comorosky

1931

25

-118

Richard

Hidalgo

2001

25

-128

Jimmy

Sheckard

1904

25

-156

 

 

Age 26

              1,983 players improved, 1995 declined, 49.8% improved.   Up to age 25, there are always more players who improve than those who decline.   At age 26 and after age 26, there are always more players who decline than those who improve.   However, more players improved their OPS at age 26 (1,983) than at any other age. 

              Twenty-four players improved by 100 or more bases at age 26, led by Darin Erstad in 2000: 

Darin

Erstad

2000

26

171

Harry

Heilmann

1921

26

159

Matt

Kemp

2011

26

151

Rico

Petrocelli

1969

26

147

Jean

Segura

2016

26

147

Jeff

Bagwell

1994

26

143

Cito

Gaston

1970

26

135

Jeff

Burroughs

1977

26

133

Heinie

Manush

1928

26

127

Kevin

McReynolds

1986

26

124

 

              Seventeen players lost 100 or more bases at age 26, led by Adrian Beltre, 198 bases:

Curt

Walker

1923

26

-106

Harlond

Clift

1939

26

-108

Doc

Farrell

1928

26

-108

J.D.

Drew

2002

26

-110

Benny

Kauff

1916

26

-116

Jim

Levey

1933

26

-122

Sixto

Lezcano

1980

26

-124

Pat

Burrell

2003

26

-124

Adam

Lind

2010

26

-135

Adrian

Beltre

2005

26

-196

 

Age 27

              1,914 players improved, 2,086 players declined, 48% improved.   However, more players declined at age 27 than at any other age, simply because the population was larger at that age than at any other.  Exactly 4,000 players either improved or declined at age 27—meaning that they were active and in the majors at both ages.  There are probably a handful who played at both ages but had exactly the same OPS at both ages.

              Seventeen players have improved by 100 or more bases at age 27, led by Stan Musial and Carl Yastrzemski.  The top four guys on this list all won the Most Valuable Player Award:

 

Stan

Musial

1948

27

169

Carl

Yastrzemski

1967

27

164

Kevin

Mitchell

1989

27

149

Brooks

Robinson

1964

27

142

Lou

Gehrig

1930

27

125

Matt

Williams

1993

27

124

Boog

Powell

1969

27

119

Rocky

Colavito

1961

27

118

Brian

Roberts

2005

27

117

Fred

Lynn

1979

27

116

 

              Twenty-five players declined at age 27 by 100 or more bases, led by John Mayberry:

Jason

Kendall

2001

27

-127

Joe

DiMaggio

1942

27

-129

Frank

Robinson

1963

27

-130

Johnny

Damon

2001

27

-136

Cito

Gaston

1971

27

-140

Jeff

Bagwell

1995

27

-147

Don

Hurst

1933

27

-148

Norm

Cash

1962

27

-160

Darin

Erstad

2001

27

-185

John

Mayberry

1976

27

-205

 

              Mayberry’s decline in 1976 is the second-worst in major league history.   I remember that season very well.   Mayberry, only 25 years old in 1975, was second in the MVP voting in 1975, which was his third 100-RBI season.   Royals fans were hoping for a dozen more.   There were all kinds of theories floating around about what was wrong with Mayberry, but we still don’t really know. 

 

Age 28

              1,789 players improved their OPS (over age 27), 2,049 declined.  47% improvement.

              Sixteen players improved by 100 or more bases at age 28, led by Mark McGwire in 1992:

Mark

McGwire

1992

28

146

Jerry

Priddy

1948

28

144

Delino

DeShields

1997

28

141

Lenny

Randle

1977

28

133

Carlos

Delgado

2000

28

127

Tommy

Holmes

1945

28

119

Wilson

Ramos

2016

28

118

Dusty

Baker

1977

28

114

Roger

Peckinpaugh

1919

28

110

Marwin

Gonzalez

2017

28

110

 

              Twenty-eight players lost 100 or more bases at age 28, led by Brook Jacoby in 1988: 

Jeff

Burroughs

1979

28

-126

Solly

Hofman

1911

28

-127

Gary

Sheffield

1997

28

-128

George

Bell

1988

28

-135

Ross

Youngs

1925

28

-137

Larry

Sheets

1988

28

-139

Jim

Gentile

1962

28

-149

Chris

Davis

2014

28

-157

Babe

Herman

1931

28

-160

Brook

Jacoby

1988

28

-177

 

Age 29

              1,663 players improved,  1871 declined.   47% improvement.

              Twenty-four players improved by 100 or more bases at age 29, led by Sammy Sosa in 1998:

 

Sammy

Sosa

1998

29

169

Dolph

Camilli

1936

29

158

Tommy

Harper

1970

29

153

Derrek

Lee

2005

29

151

Carlos

Beltran

2006

29

147

Ed

Konetchy

1915

29

131

Don

Hoak

1957

29

129

Roy

Hartzell

1911

29

124

J.T.

Snow

1997

29

119

Horace

Clarke

1969

29

117

Bill

Dickey

1936

29

117

 

              Only 19 players lost 100 or more bases at age 29, led by Tony Perez in 1971.   Note that both Perez and Bench had terrible seasons in 1971, and the Reds also lost Bobby Tolan for the season with an injury.   Bench lost 128 bases that year; that was on the age-23 list. 

 

Howard

Johnson

1990

29

-115

Dick

Green

1970

29

-118

Allen

Craig

2014

29

-119

Ralph

Kiner

1952

29

-124

Tommy

Holmes

1946

29

-126

Mickey

Vernon

1947

29

-128

Carlos

Delgado

2001

29

-131

Jimmy

Wynn

1971

29

-135

Ben

Zobrist

2010

29

-149

Tony

Perez

1971

29

-150

 

Age 30

              1,411 players improved, 1,779 declined.   44% improved. 

              Eighteen players improved by 100 or more bases at age 30, led by Jimmie Foxx in his 175-RBI season in 1938—still a Red Sox record. 

 

Jimmie

Foxx

1938

30

159

Joe

Kuhel

1936

30

138

Terry

Pendleton

1991

30

135

Pete

Runnels

1958

30

132

Aaron

Hill

2012

30

130

Bobby

Grich

1979

30

128

Cal

Ripken

1991

30

127

Jimmy

Wynn

1972

30

123

Bob

Elliott

1947

30

121

Carl

Yastrzemski

1970

30

121

 

              Twenty-nine players lost 100 or more bases at age 29, led by Rogers Hornsby in 1926.   Hornsby had hit .400 the previous two seasons and had hit 39 homers, but dropped to .317 with 11 homers in 1926—the largest season-to-season decline in major league history, if measured by this method:

 

Rich

Aurilia

2002

30

-131

Bill

Nicholson

1945

30

-133

Frank

Thomas

1998

30

-134

Hoot

Evers

1951

30

-134

Babe

Ruth

1925

30

-134

Travis

Hafner

2007

30

-147

Albert

Belle

1997

30

-147

Orlando

Cepeda

1968

30

-153

Scott

Brosius

1997

30

-166

Rogers

Hornsby

1926

30

-238

 

 

Age 31

              1,216 players improved, 1,558 declined, 44% improvement.

              Twenty-one players improved by 100 or more bases at age 31, led by Albert Belle:

             

Albert

Belle

1998

31

162

Carl

Furillo

1953

31

147

Scott

Brosius

1998

31

140

Alex

Rios

2012

31

135

Babe

Ruth

1926

31

135

Sam

Crawford

1911

31

135

Milt

Stock

1925

31

125

Roberto

Alomar

1999

31

125

Ken

Keltner

1948

31

124

Rickey

Henderson

1990

31

122

 

              Fifteen players declined by 100 or more bases at age 31, led by George Sisler in 1924.   Since Sisler missed the 1923 season with an illness, his 1924 season is being compared here to 1922, when he hit .422.   He returned from the injury in 1924. 

 

Mike

Lowell

2005

31

-118

Miguel

Cabrera

2014

31

-119

Joe

Torre

1972

31

-122

Lou

Boudreau

1949

31

-136

Red

Rolfe

1940

31

-144

Adam

Dunn

2011

31

-160

Carl

Yastrzemski

1971

31

-168

Hack

Wilson

1931

31

-174

Cal

Ripken

1992

31

-180

George

Sisler

1924

31

-196

 

Age 32

              990 players improved, 1,391 declined, 42% improvement.

              Nineteen players improved by 100 or more bases at age 32, led by Ray Powell in 1921:

 

Ray

Powell

1921

32

157

Javier

Lopez

2003

32

152

Brady

Anderson

1996

32

144

Johnny

Moore

1934

32

136

Ryan

Zimmerman

2017

32

135

Tris

Speaker

1920

32

129

Andres

Galarraga

1993

32

115

Adam

Dunn

2012

32

115

Cy

Seymour

1905

32

113

Bill

Doran

1990

32

107

Bret

Boone

2001

32

107

 

              Twenty-two players lost 100 or more bases at age 32, led by Dale Murphy in 1988, who lost 176 bases. 

 

Lee

Stanton

1978

32

-116

Sandy Jr.

Alomar

1998

32

-122

Josh

Hamilton

2013

32

-122

Aubrey

Huff

2009

32

-130

Jayson

Werth

2011

32

-131

Jack

Clark

1988

32

-134

Richie

Ashburn

1959

32

-141

Ed

Delahanty

1900

32

-143

Roy

Campanella

1954

32

-143

Dale

Murphy

1988

32

-176

 

Age 33

              857 players improved, 1,138 declined.   43% improved.

              Only five players improved by 100 or more bases at age 33, whereas 17 players declined by 100 or more:

Luis

Gonzalez

2001

33

131

Roy

Campanella

1955

33

130

Magglio

Ordonez

2007

33

130

Aubrey

Huff

2010

33

117

Dixie

Walker

1944

33

113

             

Dick

Allen

1975

33

-109

Al

Simmons

1935

33

-109

Leo

Cardenas

1972

33

-112

Jermaine

Dye

2007

33

-114

Buddy

Bell

1985

33

-114

Jose

Hernandez

2003

33

-114

Harry

Heilmann

1928

33

-115

Tim

Wallach

1991

33

-117

Brady

Anderson

1997

33

-117

Sammy

Sosa

2002

33

-121

Cy

Seymour

1906

33

-171

 

 

Age 34

              667 players improved at age 34, 951 declined.   41% improved.  Six players at age 34 improved by 100 or more bases, led by Earl Averill in 1936:

Earl

Averill

1936

34

129

Eddie

Murray

1990

34

123

Mark

McGwire

1998

34

120

Dave

Parker

1985

34

116

Steve

Finley

1999

34

106

 

              Thirteen players lost 100 or more bases at age 34, compared to age 33:

Lefty

O'Doul

1931

34

-101

Wade

Boggs

1992

34

-102

Mariano

Duncan

1997

34

-106

Darrin

Fletcher

2001

34

-108

Roy

Campanella

1956

34

-116

Miguel

Cabrera

2017

34

-121

Derrek

Lee

2010

34

-122

Robin

Yount

1990

34

-122

Ted

Simmons

1984

34

-122

Aubrey

Huff

2011

34

-124

Fred

Hartman

1902

34

-124

Luis

Gonzalez

2002

34

-140

Roberto

Alomar

2002

34

-162

 

Age 35

              503 players improved, 732 declined.   41% improved.

              Only three players improved by 100 or more bases at age 35:  Victor Martinez in 2014 (121 bases), Mickey Vernon in 1953, and Goose Goslin in 1936.    Eleven players have declined by 100 or more bases, led by Don Buford in 1972:

Moises

Alou

2002

35

-103

Pete

Runnels

1963

35

-105

Bret

Boone

2004

35

-106

Davey

Lopes

1980

35

-107

Michael

Young

2012

35

-112

Earl

Averill

1937

35

-126

Lou

Gehrig

1938

35

-127

Billy

Williams

1973

35

-129

Eddie

Murray

1991

35

-134

Ray

Durham

2007

35

-137

Don

Buford

1972

35

-144

 

Age 36

              327 players improved, 551 declined.   37% improvement.   The largest improvements were by Barry Bonds in 2001 (152 bases) and Tim Wallach in 1994.    Five players declined by 100 or more bases at age 36:

 

Mark

Teixeira

2016

36

-110

Derek

Jeter

2010

36

-116

Tom

Daly

1902

36

-125

Victor

Martinez

2015

36

-149

Max

Carey

1926

36

-152

 

Age 37

              240 players improved, 372 declined, 39% improvement.  George McQuinn, 1947, is the only player to improve by 100 bases at age 37 (111).    Six players have declined by 100 or more bases at age 37:

Luis

Aparicio

1971

37

-102

J.T.

Snow

2005

37

-102

Ken

Singleton

1984

37

-102

Chipper

Jones

2009

37

-121

Reggie

Jackson

1983

37

-127

Mark

McGwire

2001

37

-135

 

Age 38

              149 players improved, 253 declined, 37% improvement.

              No player has improved by 100 or more bases at age 38, although Gavy Cravath in 1919 improved by 98 bases.   (Modern encyclopedias list him as Gavvy, but he signed his named Gavy.)   Four players have declined by 100 or more bases at age 38:

 

Brooks

Robinson

1975

38

-100

Carlton

Fisk

1986

38

-102

Bob

Johnson

1945

38

-104

Charlie

Gehringer

1941

38

-112

 

Age 39

              98 players improved, 157 declined, 38% improvement.   No player has improved by 100 bases, age 39 compared to age 38.   Three players have declined by 100 bases at age 38—Pete Rose in 1980, Patsy Donovan in 1904, and Ted Williams in 1958.   Williams in 1958 declined by 111 bases compared to 1957—and he STILL led the league in batting average, on base percentage and OPS, even after the 111-base decline. 

             

Age 40

              61 players improved, 97 declined, 39% improvement rate.   No player improved or declined by 100 bases at age 40. 

Age 41

              33 players improved, 61 declined, 35% improved.   Ted Williams improved by 101 bases in 1960 as opposed to 1959, making him by far the oldest player to improve by 100 bases season-to-season.   Rickey Henderson declined by 112 bases at age 41, 

 

Age 42

              25 players improved, 36 declined.   41% improved.    No player improved or declined by 100 bases at age 42.  

 
 

COMMENTS (13 Comments, most recent shown first)

price499
1971 Reds crater with down seasons by Bench (lung surgery--cancer scare), Perez, and Carbo and full season missing by Tolan (tore Achilles tendon in off season team basketball game). Legend is that this season exposed the Reds team to not being suited for Riverfront Stadium after moving from Crosley Field at 1970 all-star break. Case in point was Tony Perez's decline in midseason 1970: Perez slashed .356/.439/.678 w/ 29 HR & 90 RBI (208 OPS) before all-star break. Then the Reds moved from Crosley to Riverfront: 2nd half numbers: .267/.350/.477 w/11 HR, 39 RBI & 134 OPS.
12:38 PM Aug 6th
 
klamb819
Maris: you did a much better job of making the point I was trying to make. Thanks!
11:17 PM Aug 4th
 
MarisFan61
KL: Nice points -- and I think there's even another one that you seemed to imply and which I thought you were fixing to say but then didn't -- a thing addressing my comment, a thing I didn't realize, which probably is part of the explanation for the thing I was so surprised at.

When you said "I suspect a similar process in the other direction suppresses improvement rates at younger ages"
.....I thought you were going to note the exact converse of the ever-increasing level in basic quality of the player cohorts as the age gets further and further into the 30's.

As we go from age 20 upwards into the middle 20's, the basic quality of the player cohort levels off, further and further.

The players who come to the majors at age 19 are, as a group, extraordinary players.
The ones who come up at age 20 are also pretty much that.
Those who come up at 21 are also usually pretty darn good.
The ones who come up at 22 are usually real good but we're no longer necessarily looking at the next Mike Trout, or even the next Claudell Washington. :-)
etc. etc.

The basic quality of the group gets further and further diluted. We're not looking at the same players at each next age as we go up from 19; we're looking at ever-less-good groups.

If we were doing what I sloppily thought we were doing, which was to look at the same players at each next age, it seems a safe bet that the "improvement" percentages would be higher, and maybe actually in the range that I said I'd have expected, 75-85%.​
6:45 PM Aug 3rd
 
klamb819
I agree with Maris that a sort of self-selection process is a big reason improvement rates don't drop sharply as ages increase. The pool of players beyond, say, 33, HAS to be better at each additional age in order to stay in the majors. Also, beyond, some age over 30, players are limited to one or two years of decreased production unless they're protected by big contracts or face-of-franchise status.

I suspect a similar process in the other direction suppresses improvement rates at younger ages. Which is number 3 on this list:
(1) The youngest players don't improve in straight lines to their peaks. Even Trout's OPS improved in only 4 of his 6 completed seasons. For Mathews, another great young player, it was 2 of 6.
(2) Young players often improve in great leaps, followed by smaller slippages of regression. As an example, Foxx's OPS improved in only 3 of 10 years from age 20 to 29, yet still was higher at 29 than at 19.
(3) We'd probably be surprised at the high number of players who improve at young ages but never again. I'd guess most players age 22 and under have long careers, but that's no longer true at 25, certainly, and maybe younger.

I have a vague memory that Bill has shown what percentage of players of X age are still playing at X+2 or X+3. Does anyone remember something like that? I'm pretty sure those percentages are lower than we intuitively check — a reality check that most major-league careers are brief.
5:24 PM Aug 3rd
 
MarisFan61
Re what Klamb noted, about there not being any precipitous drop in the percentages at those later ages:
It's probably related (I don't mean necessarily axiomatic!) to the successive groups at each next age being both better and better players, and less and less susceptible to aging effect.
1:43 AM Aug 3rd
 
MarisFan61
BTW, the thing about "Something nobody is talking about" wasn't a reference to anyone else's comment, only my own.
12:59 AM Aug 3rd
 
MarisFan61
A good rule of thumb that I find useful, when I hear someone start with "Something that nobody is talking about is.....," is that I can turn off the radio or just leave the room, because if nobody is talking about it, it's probably not important, and if someone thinks that something only he is talking about is important, he's probably a nut.

Nevertheless :-) .......Something nobody is talking about seems to me like the most striking thing in the data. I'm flabbergasted at it.

Would anyone have expected that the "improvement" percentages at those young ages would be so low?
I know they're not low low, but, aren't they not nearly as high as we would have expected?

From age 18 to 19, 57% of players improved.
From age 19 to 20, 64% improved.
From 20 to 21, 55%.
From 21 to 22 57%.
From 22 to 23, 54%. (Doesn't get any higher after.)

So as not to be misunderstood: I don't mean I don't believe the data, and I'm not being judgmental about players not improving enough; just surprised, extremely.
Were you all not?

Assuming I'm not the only one who's shocked at it, it's an example of how our seat-of-the-pants impressions can be way wrong and that it's only by gathering data that we can really know.
(I can't believe I'm saying this.) :-)

I've spent lots of time looking down the OPS and OPS+ columns on baseball-ref's stat pages -- hundreds of times, for sure -- and from that experience (but without tabulation), I would have thought that those above percentages would be more like in the range of 75-85%, not 54-64% -- maybe not that first one, because of the smallness of the sample, but all the rest.
12:51 AM Aug 3rd
 
klamb819
Just reading without graphing, I was struck by a different effect, focusing on age 30+. I expected to see a steady drop in improvement rates at those ages, and maybe even a precipitous drop around 33 or so, but instead it's more of a stair-stepping drop with three plateaus.

---At ages 30-33, the improvement rate drops from two years of 47 percent to a range of 42-44 percent (44, 44, 42, 43).
---At ages 34-35, the improvement rate drops from 43 percent to 41 percent at two consecutive years.
---At ages 36-40, the improvement rate drops from 41 percent to a range of 37-39 percent (37, 39, 37, 38, 39).

Maybe the severe drop I expected is better indicated by the number of players improving by at least 100 runs, from . . .
. . . 21 and 19 at ages 31 and 32, to . . .
. . . 5 and 6 at ages 33 and 34.
But I doubt if those numbers are high enough to have any statistical significance.

Age 32 was also the oldest for a breakout season with at least 100 runs' improvement. Braves center fielder
Ray Powell's highest OPS was .628 before his .830 in 1921 at 32, when he led the NL in triples and plate appearances. His OPS stayed near that level for two more years before he faded out of the league at age 35.

12:44 AM Aug 3rd
 
KaiserD2
Buried in this fascinating data, it seems to me, are some very important facts about baseball careers. It looks to me as if Bill could tease them out pretty easily from his data set and I hope he does.

A simple way to put it would be this: what is the average median age of a major league player's career as a regular?

Based on the data, it looks to me that if the average median age is 28 or higher, then the average major leaguer spends most of his career declining. And I strongly suspect that it is 28 or higher.

Note: there will be distortions in the data Bill is using for players whose mid-career point roughly coincides with a big shift from low-offense to high-offense, or vice versa.

The trick of being a major league player is to convince enough people you are good, so that some one will keep hiring you and playing you long after you have stopped being a meaningful asset, in the hopes that you might get back to your peak--which almost never happens after a certain age (unless certain chemical aids are available.) Many people continue to pull that trick off. I think the analysis I'm suggesting would confirm this.

All this is even truer for pitchers, so many of whom (way over half) burn themselves out quickly and spend long careers based on organizational hopes that they once again will be what they once were. (See Price, David, among many others.)

Again, I hope Bill might provide the data I'm asking for.

David Kaiser
8:48 AM Aug 2nd
 
doncoffin
(Having checked the math)..,Based on the data here, that's about right.
12:52 PM Jul 30th
 
bjames
So the likelihood of improving. . .having a better season. .. would be

77 - Age
---------
100

??
12:05 AM Jul 30th
 
doncoffin
I'm a very visual guy when it comes to data. So I plotted the % of players improving (vertical axis) against player age (horizontal axis). A linear trend line fits the data quite well [the simple correlation between age and % improving is -0.96 (!)] and the slope of the trend line indicated that, on average, the percent approving fell by about one percentage point for each additional year of age.​
6:36 PM Jul 28th
 
marbus1
Bernie Carbo also made the decline list for the 1971 Reds, in addition to Perez and Bench (and Tolan's injury).
6:16 PM Jul 28th
 
 
©2018 Be Jolly, Inc. All Rights Reserved.|Web site design and development by Americaneagle.com|Terms & Conditions|Privacy Policy