Understanding Baseball Statistics Abbreviations: Our EPIC Guide

Whether you are a relative newbie to the baseball scene or a long-term fan, wrapping your head around all the many different baseball statistics abbreviations is complicated.

batting stats

And one glance at the statistic abbreviations online can be enough to put you off trying to learn. Don’t let that stop you because most of them are relatively simple once you understand them.

So let’s get started!

What Are Baseball Statistics?

Every move a player makes is recorded via a series of letters or numbers that are abbreviated to make them shorter and easier to use. To understand baseball statistic abbreviations is to understand the game of baseball.

Who Uses Baseball Statistics?

Baseball statistics are used by managers, players, the front office, journalists, and fans. Managers will use player statistics, such as “batting average” to create the batting order. The front office will use detailed pitching statistics to decide which players they want to sign.

The statistics of opposing teams are studied to help players and managers decide on strategies for upcoming games.

Baseball Statistics Abbreviations

All of the abbreviations listed follow the Major League Baseball (MLB) rules. Other leagues may have different rules and abbreviations. We’ve listed these in categories.

Batting Abbreviations

  • 1B Single – The batter strikes the ball and successfully runs to first base without a defensive error.
  • 2BDouble – The batter strikes the ball and successfully runs to second base without a defensive error.
  • 3BTriple – The batter strikes the ball and successfully runs to third base without a defensive error.
  • 2S+3 – The pitcher has thrown 3+ balls after two strikes.
  • 2S+3% – The percentage of PA (plate appearance = each completed turn batting is one plate appearance) where a batter sees 2s+3.
  • 6+ – There are 6+ pitches within a plate appearance.
  • 6+% – The percentage of plate appearances with 6+ pitches.
  • AB At Bat – A player has an official plate appearance (excluding a walk, a pitch hit, obstruction, sacrifice, or interference call).
  • AB/HRAt Bats Per Home Run – The number of ABs a player has before they hit a home run.
  • aLA Average Launch Angle – An average launch angle is the vertical angle the ball leaves the player’s bat as it’s hit. The average launch angle is calculated by dividing the sum of all launch angles by all batted ball events.
  • AVG Season Batting Average – This is determined by dividing a player’s hits by their total at-bats for the season.
  • BABatting Average – This is determined by dividing a player’s hits by their total at-bats for that game.
  • BA/RSP Batting Average With Runners In Scoring Position – A player’s hits are divided by their at-bats with runners in a scoring position (runners on 2nd and/or 3rd base).
  • BABIP Batting Average On Balls In Play – This batting average is calculated using hits that are in play and fieldable. Fair-hit balls that aren’t home runs.
  • Barrel – A barrel is an “optimally” hit ball with the perfect combination of both launch angle and exit velocity.
  • BB Base On Balls – Also referred to as a “walk,” the batter receives four pitches outside of the strike zone during their plate appearance. A walk is usually classified as an unofficial AB.
  • BB/K Walks Per Strikeout – This measures a hitter’s plate discipline and knowledge of the strike zone.
  • Cent%Center Percentage – The percentage of balls that are hit into the middle of the field.
  • CI Reached On Catcher’s Interference – The catcher makes contact with the batter or his bat during a pitch, or interacts in a way that hinders the batter’s ability to hit the ball.
  • CS Caught Stealing – A runner attempts to steal and is tagged out before reaching 2nd base, 3rd base, or home plate.
  • EV Exit Velocity – Exit velocity is the measurement of the ball’s speed when it comes off the bat.
  • FCHit Into Fielders Choice – This is where an offensive player reaches a base due to the defense’s attempt to put out another baserunner.
  • FLB% Fly Ball Percentage – This is the percentage of how many a pitcher’s balls are fly balls. This is calculated by the number of fly balls divided by the balls in play.
  • GB% Ground Ball Percentage – This is the percentage of how many of a pitcher’s balls are ground balls. This is calculated by the number of ground balls divided by the balls in play.
  • GB/FB Ground Ball To Fly Ball Ratio – This is the figure of how many ground balls to fly balls the pitcher throws. This is calculated by dividing the number of ground balls by the number of fly balls.
  • GIDP Hit Into Double Plays – This is when a player hits a ground ball that results in multiple outs on the bases.
  • GITP Hit Into Triple Plays – This is when a player is grounded into a triple play.
  • GP/G Games Played – This is the number of games that have been played
  • GO/AO Groundout To Air Out Ratio – This is used to determine whether a player bats high or low hits. The number is obtained by dividing the number of groundouts by airouts.
  • GSHGrand Slam – A batter hits a home run while the bases are “loaded” (runners on 1st, 2nd, and 3rd bases).
  • H Hits – The number of hits per game.
  • Hard%Hard Contact Percentage – The percentage of balls that are considered to be hit hard.
  • HBP Hit By Pitch – When a pitcher hits a batter (who does not swing) anywhere on the body or uniform. The batter is automatically awarded 1st base.
  • HHB Hard Hit Balls – A hard hit ball is a ball with an exit velocity of 95 mph or higher. Hard hit balls are the total line drives and hard ground balls, even if they result in an out.
  • HR Home Run – When a ball is hit over the outfield fence it is a home run. It is also a home run (though rare) when a batter hits the ball and runs through all four bases without a defensive error. It is known as “an inside the park home run”
  • HR/FBHome Run To Fly Ball Rate – The percentage of how many of the pitcher’s fly balls become home runs instead of outs.
  • IFFB% Infield Fly Ball Percentage – The percentage of how many fly balls were considered infield fly balls.
  • ISO Isolated Power – Also known as Isolated Slugging. This is an indicator of a hitter’s raw power. It is calculated by taking the players batting average and subtracting the slugging percentage.
  • IBB Intentional Base On Balls – Also referred to as an “Intentional Walk” (IW). When the pitcher purposefully delivers 4 pitches out of the strike zone to avoid pitching strikes to a batter.
  • K-L Strikeouts Looking – When a batter gets called out on strikes without swinging at the ball. “caught looking”
  • LA Launch Angle – This is the vertical angle that the ball leaves a players bat once the ball has been hit.
  • LD%Line Drive Percentage – The percentage of the pitcher’s BIP that are line drives. Line drives are divided by the number of balls in play to get this calculation.
  • LOBLeft On Base – The number of runners who remain on a base when the half inning ends.
  • Med%Medium Contact Percentage – The number of medium-hit balls the batter has hit.
  • OBPOn Base Percentage – The number of times a player has reached a base safely, walked, or hit by pitch divided by the number of bats, walks, hits by pitch, and sacrifice flies.
  • Oppo%Opposite Field Percentage – The percentage of the batter’s hits that reach the opposite field from the side of the plate where they batted (right field for a right-handed batter (RHB). Left field for a left-handed batter (LHB).
  • OPS On Base Plus Slugging – A combination of the batter’s base percentage plus their slugging average.
  • PA Plate Appearances – A batter’s turn to step up to the plate to bat. Each turn counts as one plate appearance.
  • PA/BBPlate Appearances Per Walk – This is how many plate appearances a batter has compared to how many times the pitcher throws four pitches out of the strike zone where the batter does not hit the ball.
  • PIKPicked Off – A throw by a pitcher or catcher to a fielder so the fielder can tag out the baserunner, who is off the base.
  • PSPitches Seen – How many pitches a player experiences.
  • PS/PA Pitches Seen Per Plate Appearance – How many pitches are seen for each plate appearance.
  • Pull% Pull Percentage – This is the percentage of balls hit by the batter hit to the same side of the field they bat from.
  • QAB Quality at Bats – Measured by many factors such as 3 pitches after 2 strikes, 6+ pitch ABs, XBH, HHB, BB, SAC Bunt, and SAC Fly
  • QAB% – The percentage of “at bats” that are considered QABs.
  • R Runs Scored – How many times a runner has crossed home plate.
  • RBI Runs Batted In – A batter is awarded an RBI when another runner scores because of their actions during the at bat.
  • ROEReached On Error – When a batter reaches a base due to a defensive error.
  • SAC/SH Sacrifice Hits & Bunts – When a player deliberately bunts the ball before there are two outs that allow another base runner to advance to another base even if it means they are put out.
  • SF Sacrifice Flies – When a batter hits a fly-ball out to the outfield or in foul territory allowing a runner to score.
  • SLGSlugging Average – This is the total number of bases a player achieves divided by their total number of bats.
  • SO Strikeouts – When a batter accumulates three strikes during an at-bat.
  • Soft%Soft Contact Percentage – This is the percentage of soft-hit balls that a batter hits
  • TATotal Average – The total bases, steals, hit by pitch, and walks all added together minus caught stealing. This is then divided by minus hits, plus caught stealing plus grounded into double plays.
  • TBTotal Bases – The number of bases that a batter reaches safely. 1 point is awarded for first base, 2 for second, 3 for third, and 4 points for a home run.
  • WOWalk Off – When the home team has the lead in the bottom of the ninth or extra innings. Since the visiting team do not have another turn at bad the game ends.
  • wOBA Weighted On-Base Average – This is a version of on-base percentage that accounts for how a player reached base.
  • wRC+ Weighted Runs Created – This takes the statistic Runs Created and adjusts the number to account for important external factors.
  • XBH Extra base hits – This is when a batter reaches second base or further without a defensive error.
  • xwOBA Weighted On-Base Average, Expected – This an estimated wOBA based off of the batters angle launch and exit velocity.
pitching statistics using baseball abbreviations

Pitching Abbreviations

  • <13 Innings Of 13 Pitches Or Fewer
  • <3 At Bat With 3 Or Less Pitches
  • <3% 3 Or Less Pitch At Bats Per Batter Faced
  • 0BBINNZero-walk innings – This means that there have been no walks within an inning.
  • 123INN1-2-3 Innings – This is when the pitcher has to only face three batters, who had not reached the base yet.
  • 1ST2OUTInnings with 1st Two Batters Out – When the pitcher strikes out the first two batters.
  • AOAir Outs (Fly Outs) – When a batter hits the ball in the air and a defender catches the ball before it hits the ground.
  • APPAppearance – When a pitcher enters the game and faces at least one batter.
  • BAA Opponent Batting Average – This measures a pitcher’s average ability to prevent the batter from hitting the ball.
  • BABIP Opponent Batting Average On Balls In Play – This measures a pitcher’s ability to prevent the batter from hitting balls in play.
  • BBBase On Balls – When the umpire determines four pitches are outside of the strike zone and the batter does not swing at them. The batter is awarded first base.
  • BB/9Strikeouts Per 9 Innings – The average number of walks per every 9 innings.
  • BB/INNWalks Per Inning – This is the number of walks per each inning.
  • BB% Walk Percentage – The pitcher’s/hitter’s walks as a percentage of total batters faced divided by total plate appearances.
  • BBSWalk That Scored
  • BFTotal Batters Faced
  • BKBalk – When a pitcher makes an illegal hand, leg, or body movement on the mound during the pitch sequence the umpire believes is misleading to the runner. When this occurs each player on base including the batter is advanced one base.
  • BS Blown Saves – When a relief pitcher enters a game and lets the tying run score.
  • CBThe Number of Curve Balls – A curve ball is a type of pitch
    • CBS The Number Of Curve Balls Thrown For Strikes
    • CBS%Percentage of Curve Balls Thrown For Strikes
  • CG Complete Game – When the starting pitcher plays the entire game.
  • CHNumber Of Changeups – A changeup is a slow-pitched ball utilizing a special grip
  • CHS% Number Of Changeups Thrown For Strikes
  • CS Runners Caught Stealing – When a runner attempts to steal and is tagged out before reaching 2nd, 3rd, or home plate.
  • CT Number Of Cutters – A cutter is a type of a type
    • CTS Number Of Cutters Thrown For Strikes
    • CTS%Percentage Of Cutters Thrown For Strikes
  • ER Earned Run – Any run scored against the pitcher where there was no defensive error or passed ball.
  • ERA Earned Run Average – The average of earned runs is calculated by taking the total earned runs timesed by 9 and then dividing by the total number of innings.
  • FBNumber Of Fast Balls
    • FBS Number Of Fast Balls Thrown For Strikes
    • FBS%Percentage Of Fastballs Thrown For Strikes
  • FIP Fielding-Independent Pitching – These are outcomes that are not affected by fielding such as strikeouts.
  • FLB% Percentage of balls that the batter strikes in the air.
  • FPS Fast Pitch Strikes
  • FPS% Fast Pitch Strike Percentage
  • FPSH% Percentage of FPS At-Bats That Result In A Hit
  • FPSO%Percentage of FPS That Result In An Out
  • G Games – The number of times that a pitcher pitches during a season
  • Game Score – This measures the pitcher’s dominance (good or bad) in any start. The average game score is 50. Anything above 90 is considered very good and anything below 20 is considered disastrous.
  • GB%Percentage Of All The Balls Hit By The Batter That Are Hit On The Ground
  • GFGames Finished – This is credited to the last pitcher of the game providing that they did not start the game.
  • GO Ground Outs – This is a play in which a batter is put out by hitting a ball on the ground to a fielder who throwis it to or touches first base before the runner does.
  • GO/AO Ground out/Fly out ratio – This is where the total number of ground balls converted into outs is divided by the number of balls in the air that are converted into outs.
  • GS Games Started – The total number of games where the pitcher was the initial pitcher for their team.
  • H Hits Allowed – How many times the pitcher has allowed batters to hit the ball.
  • HBPHit Batters – The number of batters that step up to the plate.
  • HHB% – Percentage Of Balls That Are Hit By The Batter That Are Line Drivers Or Hard Ground Balls.
  • HLD Hold – When a relief pitcher comes into the game and maintains the lead while also outing getting at least one out.
  • HR Home Runs Allowed – How many times the pitcher allows a batter to make a home run.
  • HR/9Home Runs Per 9 Innings – The average number of home runs per 9 innings.
  • IBB Intentional Walks – The number of intentional walks issued by the pitcher.
  • IRInherited Runner – An inherited runner is a runner who is currently on a base when the relief pitcher comes into the game. Any of these runners who score against the relief pitcher do not contribute to his ERA.
  • IPInnings Pitched – The number of innings a pitcher is in the game (measured by each out in an inning. A pitcher who is taken out of the game after one out in the 4th inning has pitched 3 & 1/3 innings.)
  • IP/GS Inning Pitched/Games Started – The average number of innings pitched per each game started.
  • K Strikeout – Strikeout statistics are recorded for both pitchers and batters.
    • K%Strikeout Percentage – The pitcher’s strikeouts as a percentage of total batters faced divided by total plate appearances.
    • K/9 Strikeouts Per 9 Innings – The average amount of strikeouts per 9 innings.
    • K/BB Strikeouts Per Walk – The number of strikeouts divided by the number of walks.
    • K%-BB%Strikeout Percentage Minus Walk Percentage – This is the difference in percentage between the strikeout percentage and the walk percentage.
    • K/BF Strikeouts Per Batter Faced – How many strikeouts the pitcher gets for each batter they face.
    • K/G Strikeouts Per Regulation Game – How many strikeouts a pitcher gets per game
  • LLoss – A pitcher obtains a loss when the opposing team keeps a lead and ends up winning the game.
  • LOBRunners Left On Base – This is when a pitcher stops a baserunner from scoring.
  • LOB% – Runners Left On Base Percentage – This is the percentage of baserunners that a pitcher does not allow to score.
  • LOBBLeadoff Walk – This is when the first batter walks.
    • LOBBS Leadoff Walk That Scored – Lead-off walk that results in a score of some kind.
    • LOOLeadoff Out – This is when the first batter of the inning strikes out.
  • MV Mound Visits
  • MVR Mound Visits Remaining – This is how many mound visits are left in the game.
  • NP Number Of Pitches – This is the number of balls that a pitcher throws throughout a game including strikes, intentional and unintentional balls.
  • OS Number Of Offspeed Pitches – an offspeed pitch is a slower pitch than what the batter has been seeing (ie. changeup)
    • OSSNumber Of Offspeed Pitches Thrown For Strikes – The number of pitches thrown off speed that results in a strike.
    • OSS%Percentage Of Offspeed Pitches Thrown For Strikes
  • #P Total Pitches – This is the total number of pitches throughout a game.
  • PC-ST Pitch Count / Strikes – This is any individual pitcher’s total amount of games and the number of strikes thrown within that appearance.
  • P/BF Pitchers Per Batter Faced
  • P/IPPitches Per Inning
  • PIK/PK Runners Picked Off – A play where a runner is caught off base and is put out by a quick throw from the pitcher or catcher.
  • QSQuality Start – When a pitcher starts the game and completes a minimum of 6 innings and allows no more than three earned runs (ER).
  • R Runs Allowed – How many times a pitcher allows a batter to run to a base.
  • RW Relief Win – When a game is won by a pitcher who was not the initial pitcher.
  • S% Strike Percentage – The pitcher’s percentage of striking out batters
  • SB Stolen Bases Allowed – When the pitcher allows a baserunner to advance by taking a base to which he isn’t entitled.
  • SB%Opponent Stolen Base Percentage
  • SHO Shutout – This is the amount of games that a pitcher has allowed no runs.
  • SIERASkill Interactive ERA – An earned run average estimation that tries to more accurately capture a pitchers performance based on walks, strikeouts, homeruns, and batted ball data.
  • SL Number Of Sliders – A slider is a type of pitch.
    • SLS Number Of Sliders Thrown For Strikes
    • SLS%Percentage Of Sliders Thrown For Strikes
  • SMOpposing Batter Swings And Misses
  • SM% Percentage Of Total Pitches Thar Are Swings And Misses
  • SOStrikeout – The pitcher is credited a strikeout when the batter receives 3 strikes while they are pitching.
  • SRSpin Rate – The rate at which the ball spins once it is released from the pitcher’s hand – measured in revolutions per minute.
  • SVSave – A save is credited to the pitcher when they enter the game with the lead and they are able to maintain the lead. The criteria for a save are as follows: the pitcher is not considered the “winning pitcher”, the lead is 3 runs or fewer when they enter the game, the potential tying run is on base, at bat, or on deck.
    • SV% Save Percentage
    • SVO Save Opportunities
  • TB Total Balls – The number of bases a player gains with hits.
  • TBFTotal Batters Faced – The number of batters that a pitcher has faced.
  • TS Total Strikes
  • UERUnearned Run – Arun where the batter scores because of a defensive error or a passed ball.
  • VELO Velocity – This is the maximum speed of a pitchers throw at any point from release to crossing the home plate.
  • W Win – A pitcher is credited a win when their team has a lead after five completed innings and goes on to win the entire game.
  • W+S Wins In Relief Plus Saves
  • WEAK%Percentage Of Balls Weakly Hit By The Batter (flyballs & groundballs)
  • WHIP Walks And Hits Pers Innings Pitched – The average amount of hits and walks that a pitcher allows in an inning.
  • WPCTWinning Percentage – Calculated by the total number of wins divided by the total number of decisions (both wins and losses)
  • WPWild Pitch – When the pitcher throws a ball that is far enough away from the strike zone that the catcher has trouble fielding it, and it allows runners to advance to the next base or bases. If runners do not advance, it is not considered a wild pitch.
  • xFIP Expected Fielding Independent Pitching – An estimation of a player’s earned run average taking into consideration strikots, home runs, and walks assuming league average results on balls in play.
Understanding Baseball Statistic Abbreviations

Defense/Fielding Abbreviations

  • AAssist – The number of outs recorded on a play where the player fielded the ball.
  • DERDefensive Efficiency Rating – The number of balls in play that the defensive team can convert into outs.
  • DPDouble Play – When two runners are out in the same play.
  • DRS Defensive Runs Saved – This is when a player’s defensive performance is measured by how many runs the defender saves. Errors, range, outfield arm, and double-play ability are factors that are all taken into account.
  • E Error – Any time a defensive player fails to make a play that is reasonably expected to be made.
  • FP/FPCTFielding Percentage – This is the total number of plays that have been made minus the number of errors made, and then divided by the number of chances throughout the game.
  • INN Innings – The total number of innings that a player stays in one position/role.
  • OFAOutfield Assist – When an outfielder throws a ball to an infielder that results in an out.
  • OOut – When a runner is caught out and doesn’t make it safely to their base.
  • PBPass Ball – When the catcher can not hold onto a pitch and one or more players reach or move up a base.
  • POPutout – When a fielder creates an out by forceout, catching a 3rd strike, catching a batted ball, or tagging a runner.
  • TC Total Chances
  • TPTriple Plays – Three offensive players are out in a single play.
  • UZRUltimate Zone Rating – A player’s entire defensive performance is measured by how many runs the defender can save. It also takes range, errors, outfield arm, and double-play ability into account.

Base Running Abbreviations

  • CSCaught Stealing – If a runner tries to steal a base but is tagged out, they are “caught stealing”.
  • R Runs – Every time a base runner crosses home plate a “run” is scored.
  • SB Stolen Base – When a runner progresses at least one base while the defensive team has control of the ball.
    • SB% Stolen Base Percentage – The amount of successful stolen bases divided by attempted stolen bases.
    • SBA/ATT Stolen Base Attempts – The number of times a runner has tried to steal a base.

Catching Abbreviations

  • CI Batter Advances On Catchers Interference
  • CS Runners Caught Stealing
  • CS% Runners Caught Stealing Percentage
  • INNInnings Caught
  • PBPassed Balls Allowed
  • PIKRunners Picked Off
  • SBStolen Bases Allowed
  • SB-ATT Stolen Bases Allowed Minus Stealing Attempts

General/Team Abbreviations

  • ARBArbitration Eligible – You may also see Pre-Arb, which is before a player is eligible. Pre-Arb followed by a number is the year that a player is in arbitration.
  • E# Elimination Number – The number of losses needed by teams in each division that will eliminate them from playing in the playoffs.
  • RS Run Support – The number of runs the pitcher’s team scored collectively throughout their appearances.
  • RS/9 Run Support Per 9 Innings – The RS for every 9 innings.
  • Run Differential – The total number of runs scored minus the total number of runs allowed.
  • WARWins Above Replacement – Comparing the amount of wins a player has versus a replacement players wins of the same position.
  • WCGBWild Card Games Back – This shows how many games back a team is from the Wild Card spot
  • WPAWin Probablity Added – The percent change in a team’s chance of winning from each game to the next.

Baseball Postions By Number

  1. Pitcher
  2. Catcher
  3. First Base
  4. Second Base
  5. Third Base
  6. Shortstop
  7. Left Field
  8. Center Field
  9. Right Field
Understanding Baseball Statistic Abbreviations

MLB Historical Statistics – Best Baseball Statistics Of All Time

Batting Average

  1. Ty Cobb – .366
  2. Rogers Hornsby – .358
  3. Joe Jackson – .356
  4. Ed Delahanty – .346
  5. Tris Speaker – .345

Home Runs

  1. Barry Bonds – 762
  2. Hank Aaron – 755
  3. Babe Ruth – 714
  4. Alex Rodriguez – 696
  5. Albert Pujois – 694


  1. Pete Rose – 4,256
  2. Ty Cobb – 4,189
  3. Hank Aaron – 3,771
  4. Stan Musial – 3,630
  5. Tris Speaker – 3,514


  1. Cy Young – 511
  2. Walter Johnson – 417
  3. Pete Alexander – 373
  4. Chrsty Mathewson – 373
  5. Warren Spahn – 363


  1. Nolan Ryan – 5,714
  2. Randy Johnson – 4,875
  3. Roger Clemens – 4,672
  4. Steve Carlton – 4,136
  5. Bert Blyleven – 3,701


  1. Mariano Rivera – 652
  2. Trevor Hoffman – 601
  3. Lee Smith – 478
  4. Francisco Rodriguez – 437
  5. John Franco – 424

Frequently Asked Questions

What Is The Most Important Baseball Stat?

While all baseball statistics matter, batting average has long been one of the most popular and well-respected baseball statistics.

Who Holds the Record for the Best Batting Average In Baseball History?

Ty Cobb of the Detroit Tigers had a lifetime batting average of .366 over 24 seasons.

Why Are Baseball Statistics Important?

Baseball statistics are important because they are used to measure players’ capabilities.

When players are being signed for teams these statistics highlight their strengths and weaknesses. When games are televised these statistics are also pretty crucial for the game commentators.

How Many Stats Are There In Baseball?

In total, there are 121 different baseball statistics. Of those 72 are considered standard and 49 are considered advanced.

Who Started Baseball Statistics?

In the mid-19th century, a man named Henry Chadwick was credited with developing the box score and his tabulation of hits, home runs, and total bases. This led to the formulation of metrics that we use still to this day.

What Year Was The First Collection Of Baseball Statistics Published?

It was 1969 when The Baseball Encyclopedia was first published.

Final Thoughts

Hopefully, you now have a much better understanding of what most of the baseball statistics abbreviations mean.

I tried to get every last little piece of information on baseball statistics that I can offer you into one article. So you can always pop back and reference an abbreviation if you need to refresh yourself.

Thank you for joining me on this ultimate guide to baseball statistics – go forth and share your newly gained knowledge!

Matt Crouch
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