How to manage equal playing time in Football (Soccer)

Equal Playing time Equation example:
Total number of Minutes available (game length x total positions)
50mins x 7 positions = 350 mins
350 minus the Goalkeepers minutes (350-50) = 300 mins
300 divided by the total number of available players (10).
300 divide by 10 = 30.
Each outfield player will play 30 minutes of the game.

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All squad numbers are including not including Goalkeepers in minutes or team numbers Example: 5 A SIDE – 5 Players (Goalkeeper Plus 5 Players) = 32 Minutes each

5 A SIDE: (40-Minute Game)
5 Players (1 Sub) – 32 Mins each
6 Players (2 Subs) – 27 Mins each
7 Players (3 Subs) – 23 Mins each
8 Players (4 Subs) – 20 Mins each

7 A SIDE: (50-Minute Game)
7 Players (1 Sub) – 43 Mins each
8 Players (2 Subs) – 37.5 Mins each
9 Players (3 Subs) – 33 Mins each
10 Players (4 Subs) – 30 Mins each
11 Players (5 Subs) 27 Mins each

9 A SIDE: (60-Minute Game)
9 Players (1 Sub) – 53 minutes each
10 Players (2 Subs) – 48 minutes each
11 Players ( 3 Subs) – 43 minutes each
12 Players – (4 Subs) – 40 Minutes each

11 A SIDE: (80-Minute Game)
11 Players (1 Sub) – 73 minutes each
12 Players (2 Subs) – 66 minutes each
13 Players (3 Subs)- 61minutes each
14 Players (4 Subs) – 57 minutes each
15 Players (5 Subs) – 53 minutes each

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