The Evolution of the Strikeout: How Often Batters Strike Out, Decade by Decade
League strikeout rates from 1900 to 2025, decade by decade, with the three snapshot seasons of 1920, 1968 and 2019 as anchors: how the average team went from under 3 strikeouts a game to nearly 9, and why.
In 1920, the average major-league team struck out 2.95 times a game. In 2019 it struck out 8.81 times. That is a threefold increase in a century, and it did not happen in one jump or in a straight line. It rose through the 1950s, jumped in the early 1960s, eased in the 1970s, climbed again from the 1990s, and then, in the 2010s, went up faster than at any earlier time. By 2018, for the first time in the American and National League record, batters struck out more often than they got hits.
This article tracks that rise decade by decade using the historical record, anchors it on three seasons for which we have full sheets (1920, 1968 and 2019), and explains the rule changes, the home-run era and the pitching changes that move the numbers. It also says clearly what the numbers do not prove. The rate tells you what happened; it does not by itself tell you why.
How to read the numbers
The figure used throughout is strikeouts per team-game: the total strikeouts by a team's batters divided by the games the team played. It is a count of batter strikeouts for one side. A single nine-inning game between two teams therefore has about twice that many strikeouts in total. The numbers below cover the American and National Leagues only; the Negro leagues that the historical record carries from 1920 to 1948 are listed separately and are not in these averages.
A "per game" rate is the simplest measure, and it has a small problem: it depends on how many batters come to the plate, which depends on how many runs score and how many players reach base. A better measure, used in the second table, is strikeouts per plate appearance. The club table in the historical record does not carry sacrifice bunts, so the plate-appearance figures here are computed from at-bats, walks, hit batters and sacrifice flies. They are very slightly high, and the direction of the trend is not affected.
Decade by decade
| Decade | SO per team-game | HR per team-game | AL+NL batting average |
|---|---|---|---|
| 1900s | 3.50 | 0.14 | .253 |
| 1910s | 3.68 | 0.17 | .255 |
| 1920s | 2.81 | 0.40 | .285 |
| 1930s | 3.32 | 0.55 | .279 |
| 1940s | 3.55 | 0.52 | .260 |
| 1950s | 4.40 | 0.84 | .259 |
| 1960s | 5.72 | 0.82 | .249 |
| 1970s | 5.14 | 0.75 | .256 |
| 1980s | 5.36 | 0.81 | .259 |
| 1990s | 6.15 | 0.96 | .265 |
| 2000s | 6.56 | 1.07 | .265 |
| 2010s | 7.82 | 1.07 | .254 |
| 2020 to 2025 | 8.52 | 1.17 | .245 |
Read down the middle column and the pattern is plain. The 1920s are the low point at 2.81. The numbers then climb in nearly every decade, with one pause in the 1970s, and each decade from the 1990s on sets a new high. The right-hand column shows a quieter change: the league batting average falls from a high of .285 in the 1920s to .245 in the first six seasons of the 2020s. Batters are striking out more and hitting for a lower average, and the extra power does not fully offset it.
1900 to 1919: the dead-ball strikeout
The early twentieth century had a strikeout rate of 3.5 to 3.7 per team-game, which is higher than the 1920s. That is a surprise to modern readers, who think of the dead-ball era as one of contact hitting. The explanation is partly about rules. The National League began counting a foul ball as a strike in 1901, and the American League did so in 1903: a foul with fewer than two strikes now added a strike to the count. Before then a batter could foul off pitches for as long as he liked without penalty, and strikeouts were rarer. The data fit the change, with 3.15 strikeouts per team-game in 1901 against 2.09 in 1894.
The other part is the way pitchers worked. Spitballs, scuffed balls and other doctored pitches were legal, and the ball stayed in play until it was badly worn. Home runs were extremely rare, 0.14 per team-game in the 1900s, so a batter gained little by swinging hard. Strikeouts in this period came from pitchers who were hard to square up, not from hitters trading contact for power.
The lowest strikeout rate in the historical record is 1.13 per team-game in 1876, the National League's first season. That earlier game had different rules for balls and strikes and is not part of the decade table above.
1920: the start of the live-ball low
The 1920 season is the first anchor. The league scored 4.36 runs per team-game, hit 0.26 home runs per team-game and struck out 2.95 times per team-game. Babe Ruth hit 54 home runs, and the runner-up in the majors had 19. George Sisler hit .407 and had 257 hits. Rogers Hornsby won the National League batting title at .370. The leading strikeout pitcher in the majors, Pete Alexander, had 173 for the season.
The spitball was banned that year, with a small group of existing pitchers allowed to continue using it, and, as is commonly noted, dirty or damaged balls were replaced more often. The league's strikeout rate fell from 3.87 in 1910 to 2.95 in 1920 and then to 2.70 in 1924 and 2.72 in 1925, the lowest figures since the National League's one-league year of 1900. A batter struck out in about 8 percent of his plate appearances in 1920.
The leaders confirm the era. In 1930, the National League slugger Hack Wilson hit 56 home runs and drove in 191 runs while leading the majors in strikeouts with 84. The major-league strikeout leader among batters had 114 in 1950, 189 in 1970 (Bobby Bonds), 182 in 1990 (Cecil Fielder) and 211 in 2010 (Mark Reynolds), and in 2025 James Wood struck out 221 times.
1930 to 1959: the long, slow climb
From the 1930s onward the rate crept up almost every year. The 1930s average 3.32, the 1940s 3.55, and the 1950s 4.40. In 1941 the league struck out 3.55 times per team-game; Joe DiMaggio struck out only 13 times that year while hitting 30 home runs. The decade-by-decade change was small but steady, and the likeliest cause is that batters were learning that power paid. Home runs per team-game rose from 0.40 in the 1920s to 0.84 in the 1950s.
The change shows in the share of plate appearances that ended in a walk, a strikeout or a home run, the three outcomes that involve no fielders. In 1920 that share was about 16 percent. By 1941 it was 20 percent, and by 1968 it was 26 percent. These are sometimes called the three true outcomes, and they are the best single indicator of a game that is moving away from balls in play.
The 1950s crossed a threshold: 5.09 strikeouts per team-game in 1959, the first season above 5, and 5.18 in 1960. That is also the period in which relief pitchers were becoming specialists. A starter tires and tends to be hit harder the third time through a lineup, while a reliever who comes in for an inning can throw at full effort against hitters who have not seen him. The historical data cannot show the cause, but the shape of the curve fits it.
1961 to 1969: the pitcher's decade
The 1960s have the highest strikeout rate in the data until the 1990s: 5.72 per team-game on average, with a peak of 5.99 in 1967. The jump from 5.42 in 1962 to 5.80 in 1963 is the largest one-year rise of the period, and it coincides with the larger strike zone adopted for 1963. League expansion in 1961 and 1962 and the growing role of relievers may also have contributed.
The 1968 season is the second anchor. Teams scored 3.42 runs per game, hit 0.61 home runs per game and struck out 5.89 times per game. Bob Gibson finished with a 1.12 earned run average, and Denny McLain won 31 games. Carl Yastrzemski won the American League batting title with a .301 average, among the lowest ever to lead a league. Sam McDowell struck out 283 batters to lead the American League, and the National League's top strikeout pitcher in 1968 was Gibson with 268. In 1965 Sandy Koufax had struck out 382, which stood as the modern single-season record until Nolan Ryan's 383 in 1973.
Baseball's response was to lower the mound and shrink the strike zone for 1969. The result in the historical table is clear but modest: 5.77 strikeouts per team-game in 1969 against 5.89 in 1968, and 0.80 home runs against 0.61. The more dramatic change was in scoring, which rose from 3.42 runs per team-game in 1968 to 4.07 in 1969. For more on the 1968 pitching standard, see the lowest ERAs in baseball history.
1970 to 1989: the plateau
The strikeout rate fell for the first time in decades: 5.75 in 1970, 5.41 in 1971, 5.24 in 1973, 4.98 in 1975 and 4.80 in 1980. The two decades average 5.14 and 5.36. One factor often cited for the dip is that starters worked deeper into games than they would later; the workload figures are in our piece on the complete game.
Reggie Jackson, whose career total of 2,597 strikeouts is the highest for a batter in the historical record, played through this period. He is a reminder that the high-strikeout slugger was not new, only less common. Even so, the rate never again fell back to the levels of the 1940s.
1990 to 2009: strikeouts and home runs together
The 1990s average 6.15 per team-game and the 2000s 6.56. In this period, both strikeouts and home runs rose together, which had not been true of every earlier stretch. The league hit 1.17 home runs per team-game in 2000, the highest rate in the data up to that point, and it struck out 6.45 times. Scoring was also at a high, 5.14 runs per team-game. This was the era in which offence was high enough that a strikeout seemed a small price for a home run.
By 2005 the numbers had eased slightly (6.30 strikeouts and 1.03 home runs per team-game), and by 2010 the strikeout rate had resumed its climb to 7.06 while home runs had fallen to 0.95. That is the first sign of a different regime: strikeouts rising without a matching rise in power.
2010 to 2019: the steepest climb
The 2010s are where the rate leaves its old range. It rises from 7.06 in 2010 to 7.71 in 2015, 8.03 in 2016, 8.25 in 2017, 8.48 in 2018 and 8.81 in 2019. In 2018 total strikeouts in the American and National Leagues (41,207) exceeded total hits (41,019) for the first time in the record. By 2019, nearly 23 of every 100 plate appearances ended in a strikeout, and about 35 in every 100 ended in one of the three true outcomes.
The 2019 season is the third anchor, and it was a season of extremes in other ways. Teams averaged 4.83 runs and 1.39 home runs per team-game, the highest home-run rate in the record. Pete Alonso hit 53 home runs as a rookie to lead the majors, and Gerrit Cole struck out 326 batters. All ten of the highest single-season strikeout totals by a batter in the historical data come from 2009 or later, and the three highest through 2025 are Mark Reynolds (223 in 2009), Adam Dunn (222 in 2012) and James Wood (221 in 2025).
| Season | SO per team-game | Strikeouts per 100 PA | Walks, strikeouts and homers per 100 PA |
|---|---|---|---|
| 1920 | 2.95 | 8.0 | 16.2 |
| 1968 | 5.89 | 16.3 | 25.7 |
| 2019 | 8.81 | 23.1 | 35.3 |
| 2025 | 8.36 | 22.3 | 33.8 |
2020 to 2025: a plateau or a turn?
The most recent seasons show a leveling. The league struck out 8.68 times per team-game in 2020 and 2021, 8.40 in 2022, 8.61 in 2023, 8.48 in 2024 and 8.36 in 2025. That is the lowest figure since 2017, though still far above any earlier decade. The batting average in 2025 was .245, which is among the lowest in the record.
Several rule changes arrived in this window. The designated hitter became universal in 2022, which removed pitchers from the lineup, and pitchers had struck out often when they batted. A pitch timer began in 2023, together with larger bases and limits on defensive shifts. The numbers do not allow us to credit any one change; the dip in 2022 is consistent with the universal designated hitter, and the slight rise in 2023 shows that the other changes did not reverse the trend. It is too early to call a turn, and this article makes no prediction.
Why it happened
Writers and analysts have offered several explanations, and the data supports some of them better than others.
- Power pays. As home runs rose, batters accepted more strikeouts in exchange for more extra-base hits. The home-run rate and the strikeout rate rose together through most of the century, though not in the 2010s.
- Specialized pitching. Relievers who throw one inning at full effort are harder to hit than starters in their third turn through the order. The decline of the complete game is the other side of this change.
- Rules and the zone. The 1963 enlargement and 1969 reduction of the strike zone show up in the data, which is the cleanest evidence in this article that rules matter.
- Information. Teams now know where a pitcher is weakest and how a batter's swing path affects results. This one is harder to measure in a database of counting stats, and the explanation is plausible rather than proved.
What the data cannot tell us is how much of the rise reflects better pitching and how much reflects worse contact skills. They are not the same thing, and the numbers here combine them.
What a strikeout costs
A strikeout is an out, like any other, but it is a worse out than most. A ball put in play can advance a runner, produce a sacrifice fly, or reach base on an error; a strikeout does none of those things. The guide to tagging up and the sacrifice fly explains one of the plays a strikeout gives up. The difference is small per plate appearance, and the answer to whether a strikeout is worth the extra power depends on how much power the batter adds.
Common questions
What was the lowest strikeout rate in modern baseball? In the American and National Leagues, 2.70 strikeouts per team-game in 1924 is the lowest single-year figure after 1900 in the historical data, with 2.72 in 1925 close behind. Earlier years were lower, with 1.13 in 1876.
What was the highest? 8.81 in 2019, with 8.68 in 2020 and 2021 close behind.
Did strikeouts go up in the steroid era? The rate rose through the 1990s and 2000s, from 6.15 to 6.56 per team-game across the two decades. They rose much faster in the 2010s, which is a different period. The data do not separate the causes.
Who has the most career strikeouts? Among pitchers, Nolan Ryan with 5,714. Among batters, Reggie Jackson with 2,597.
Do Negro league strikeouts count? They are in the historical record for 1920 to 1948 under separate league codes and are not in the averages above. The story of how those statistics joined the record is in how Negro league statistics joined the major-league record.
Where to go next
If a strikeout total makes you curious about the pitchers behind it, read about no-hitters and perfect games and about the league that ran alongside the majors in the history of the Negro Leagues. Use the leaders page to look up single-season strikeout leaders, or browse the stats and analytics topic page.