By Dan Durkin-

(CBS) Per Article 28 of the NFL’s Collective Bargaining Agreement, a performance-based pool of money is created and distributed league-wide each season. This fund is a player benefit, and thus it doesn’t affect a team’s salary cap.

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To be eligible for the benefit, a player must have played at least one snap in the regular system. The system rewards players with lower salaries.

Two variables are used to determine a player’s index — playtime percentage divided by player compensation. Playtime percentage is determined by calculating the total number of snaps a player plays on offense, defense and special teams. Player compensation is calculated by adding his full salary and bonuses, plus incentives.

The player index total is then multiplied against the total performance based pool amount, which is $3.63 million for 2015.

Here are the Bears’ top 10 performance-based players from the 2014 season:

— Offensive lineman Michael Ola ($266,554.96)

— Linebacker Christian Jones ($222,364.96)

— Offensive tackle Jordan Mills ($204,711.83)

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— Safety Brock Vereen ($190,471.64)

— Cornerback Demontre Hurst ($159,572.19)

— Tight end Dante Rosario ($132,827.94)

— Linebacker Jon Bostic ($121,400.87)

— Defensive tackle Will Sutton ($115,691.89)

— Wide receiver Alshon Jeffery ($100,430.52)

— Safety Ryan Mundy ($98,246.47)

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Dan Durkin covers the Bears for CBSChicago.com and is a frequent contributor to 670 The Score. Follow him on Twitter at @djdurkin.