General Statistics

• 1). Determine a team's winning percentage by dividing the team's number of wins by the number of games that the team has played. For example, a team that has 11 wins and 5 losses has a winning percentage of .688 because wins -- 11 -- divided by number of games -- 16 -- is .6875. The winning percentage is rounded to three places, so .6875 becomes .688.
  
  
• 2). Calculate a quarterback's average yards per pass attempt. To determine this statistic, divide the total number of yards by the number of attempts. If QB Aaron Rodgers has 3,693 passing yards on 447 attempts, his average is 8.3 yards per attempt.
  
  
• 3). Calculate a running back's yards per carry by dividing the number of yards he gains by the number of times the ball is handed off to him. In 2010, Jamaal Charles of the Kansas City Chiefs rushed for 1,467 yards on 230 carries. Divide the 1,467 total yards by 230 carries to get 6.378. Round up to one decimal point, and Charles' yards per carry is 6.4.
  
  
• 4). Determine a wide receiver's yards per catch by dividing the number of yards he gains by the number of passes that he catches. In 2010, Reggie Wayne of the Colts caught 111 passes for 1,355 yards. Divide 1,355 total yards by 111 catches to get 12.207.
  
  Round up, and Wayne's average is 12.2 yards per catch.
  
  
• 5). Determine a team's success on third downs by figuring out its third-down conversion rate. For example, a team is 7-for-12 on third-down conversions. Divide the seven conversions by 12 attempts to get .583333, or 58 percent.
  
  
• 6). Add up the number of passing, rushing and receiving yards a player has in a game to determine the player's total yards. For example, a player is credited with 10 passing yards, 100 rushing yards and 15 receiving yards in a game. Add the three numbers together to arrive at 125 total yards.
  
  

QB Passer Rating

• 1). Determine a quarterback's passer rating to provide a comparison to other quarterbacks. In this example, we'll use Peyton Manning's 2004 season. That year, his completion percentage was 67.6 percent, yards per attempt was 9.2, percentage of touchdown passes was 9.9 and percentage of interceptions was 2.0. Subtract 30 from the completion percentage of 67.6, then multiply the result, 37.6, by .05 to get 1.88.
  
  
• 2). Subtract 3 yards from the yards per attempt, 9.2, to get 6.2 and multiply the result by .25 to get 1.55.
  
  
• 3). Multiply Manning's touchdown percentage of 9.9 by .2 to get 1.98.
  
  
• 4). Multiply the interception percentage of 2.0 by .25 to 0.5. Subtract 0.5 from 2.375 to get 1.875.
  
  
• 5). Add the sum of the four calculations together: 1.88 + 1.55 + 1.98 + 1.875 = 7.285. Divide the result, 7.285, by 6 to get 1.214. Multiply the final result by 100 to arrive at Peyton Manning's passer rating for 2004: 121.4