Football Analytics Glossary
A comprehensive reference guide to key terms, metrics, and concepts in football analytics. Use the search box or alphabet navigation to find specific terms.
A
Air Yards
AY
The distance a pass travels in the air from the line of scrimmage to the point where it is caught or incomplete. Air yards measure the depth of passing attempts and help distinguish between quarterback arm strength and receiver yards after catch (YAC) contributions.
Formula:
Air Yards = Yard line where ball is caught - Line of scrimmage
Example:
A quarterback throws from the 30-yard line and the receiver catches at the 45-yard line: Air Yards = 45 - 30 = 15 yards
Average Depth of Target
aDOT
The average air yards of all pass attempts by a quarterback or targeted to a receiver. aDOT helps characterize passing attack aggressiveness and receiver roles. A high aDOT indicates deep passing, while low aDOT suggests short, quick passes.
Formula:
aDOT = Total Air Yards / Total Pass Attempts
Example:
A quarterback throws 400 passes with 3,600 total air yards: aDOT = 3,600 / 400 = 9.0 yards per attempt
C
Completion Percentage Over Expected
CPOE
A measure of quarterback accuracy that compares actual completion percentage to the expected completion percentage based on factors like air yards, pass location, and pressure. Positive CPOE indicates better-than-expected accuracy, while negative CPOE suggests worse-than-expected accuracy.
Formula:
CPOE = Actual Completion % - Expected Completion %
Example:
A QB completes 68% of passes when the model expected 64%: CPOE = 68% - 64% = +4.0%
Cover 0
A defensive coverage scheme with no deep safety help, featuring all-out man-to-man coverage with aggressive pass rush. Extremely high-risk, high-reward coverage typically used in obvious passing situations or as a surprise tactic.
Example:
On 3rd and long, the defense shows Cover 0 to bring pressure with 6+ rushers, leaving receivers in one-on-one coverage with no safety help over the top.
Cover 1
Man-to-man coverage with a single deep safety providing help over the top. Allows aggressive man coverage underneath while maintaining some deep protection. Often used to counter vertical passing attacks.
Cover 2
Zone coverage with two deep safeties each responsible for half the deep field and five underneath defenders in zone coverage. Effective against vertical passes but vulnerable to intermediate routes and run game.
Cover 3
Zone coverage with three deep defenders splitting the field into thirds and four underneath zone defenders. Balanced coverage that protects against deep passes while maintaining adequate underneath coverage.
D
Defense-adjusted Value Over Average
DVOA
A metric developed by Football Outsiders that measures team and player efficiency by comparing performance on each play to a baseline average, adjusting for situation (down, distance, field position) and opponent quality. Higher DVOA indicates better performance.
E
Expected Points
EP
The average number of points a team would be expected to score on their current drive given the down, distance, and field position. EP provides context for evaluating individual play outcomes and serves as the foundation for EPA calculations.
Formula:
EP is calculated using historical data and logistic regression models based on game situation variables (down, distance, yard line, time remaining)
Example:
1st and 10 from opponent's 40-yard line typically has an EP of about +2.0 points, meaning offenses score an average of 2 points from this situation.
Expected Points Added
EPA
The difference between the Expected Points at the start of a play and the Expected Points at the end of the play. EPA measures the value of individual plays in terms of point contribution, accounting for situation and context. Positive EPA indicates a successful play that improved scoring chances.
Formula:
EPA = EP(end of play) - EP(start of play)
Example:
Starting EP of +1.5 → After a 15-yard gain, EP becomes +2.8 → EPA = 2.8 - 1.5 = +1.3
P
Pass Rush Win Rate
PRWR
The percentage of pass rushes where a defender beats their blocker within 2.5 seconds. Measured using NFL Next Gen Stats tracking data, this metric evaluates pass rushing effectiveness independent of sacks or pressures.
Formula:
PRWR = (Rush Wins / Total Pass Rush Snaps) × 100%
Play Action
A passing play that begins with a fake handoff to a running back to deceive the defense. Play action is typically more effective than standard dropback passes, generating higher yards per attempt and lower pressure rates due to hesitation by defenders.
Example:
Play action passes average about 1.0 EPA higher than standard dropbacks and result in 30% fewer pressures.
Pressure Rate
The percentage of dropbacks where the quarterback faces pressure from the pass rush (hit, hurry, or sack). Pressure rate is a key indicator of offensive line performance and affects all aspects of passing efficiency.
Formula:
Pressure Rate = (Pressures / Dropbacks) × 100%
R
Run Stuff Rate
RSR
The percentage of running plays stopped at or behind the line of scrimmage. Run stuff rate measures defensive run stopping ability and offensive line run blocking effectiveness. Higher rates indicate better defensive performance.
Formula:
RSR = (Runs ≤ 0 yards / Total Runs) × 100%
S
Success Rate
The percentage of plays that achieve a successful outcome based on down and distance thresholds. A play is typically considered successful if it gains 40% of needed yards on 1st down, 60% on 2nd down, or 100% on 3rd/4th down. Success rate emphasizes consistency and efficiency.
Formula:
Success Rate = (Successful Plays / Total Plays) × 100%Where Success = 40% of yards on 1st, 60% on 2nd, 100% on 3rd/4th
Example:
On 1st and 10, gaining 4+ yards is successful. On 2nd and 7, gaining 5+ yards is successful.
Stacked Box
A defensive alignment with 8 or more defenders positioned within the tackle box (area between offensive tackles and within 5 yards of line of scrimmage). Stacked boxes are used to stop the run but leave the defense vulnerable to passes, particularly deep shots.
Example:
Teams face stacked boxes on about 25% of plays, with rates increasing to 40%+ for elite running teams.
T
Target Share
The percentage of a team's total pass targets thrown to a specific receiver. Target share indicates a receiver's role in the passing offense and opportunity for production. Elite receivers typically command 25%+ target share.
Formula:
Target Share = (Player Targets / Team Total Targets) × 100%
Example:
A receiver with 150 targets on a team with 600 total targets: Target Share = 150/600 = 25%
Time to Throw
TTT
The average time elapsed from snap to throw for a quarterback, measured using Next Gen Stats tracking data. TTT indicates quarterback decision-making speed and offensive scheme design. NFL average is approximately 2.7 seconds.
True Completion Percentage
TCP
Completion percentage that excludes drops, throwaways, spikes, and passes defensed at the line of scrimmage. TCP better isolates quarterback accuracy by removing outcomes outside quarterback control.
Formula:
TCP = Completions / (Attempts - Drops - Spikes - Throwaways - Batted)
W
Win Probability
WP
The probability that a team will win the game given the current score, time remaining, field position, down, and distance. WP ranges from 0% to 100% and is calculated using historical game outcomes from similar situations.
Example:
Leading by 7 points with 2 minutes remaining and possession: WP ≈ 95%. Trailing by 3 with 2 minutes and no timeouts: WP ≈ 25%.
Win Probability Added
WPA
The change in win probability from the start to the end of a play. WPA measures play impact in terms of winning the game rather than points. Late-game plays have higher WPA magnitude than early-game plays due to context sensitivity.
Formula:
WPA = WP(end of play) - WP(start of play)
Example:
A game-winning touchdown with 10 seconds left might have WPA = +50% (from 50% to 100% win probability).
Y
Yards After Catch
YAC
The yards gained by a receiver after catching the ball, calculated as total receiving yards minus air yards. YAC measures receiver elusiveness, blocking, and scheme design effectiveness. It's influenced by both receiver skill and pass depth.
Formula:
YAC = Total Receiving Yards - Air Yards
Example:
A 25-yard completion with 10 air yards results in 15 YAC.
Yards Per Route Run
YPRR
The average receiving yards gained per pass route run by a receiver. YPRR is considered one of the best measures of receiver efficiency as it accounts for all opportunities (routes run) rather than just targets or receptions. Elite receivers exceed 2.0 YPRR.
Formula:
YPRR = Total Receiving Yards / Total Routes Run
Example:
A receiver with 1,200 yards on 500 routes: YPRR = 1,200 / 500 = 2.4