Credit Earn Rate
There's a few things to bear in mind when it comes to Credit earnings, things that we don't (yet) communicate properly in-game:
The base credit earn rate is 12/min (it is less if a server has fewer than 10 players)
Completing a match and losing (spent the most time on losing team) gives you a +10% bonus to earnings
Completing a match and winning (spent the most time on winning team) gives you a +30% bonus
Completing a match and having the highest XP on the server gives you a +20% bonus and this linearly scales across the entire server:
The player at the bottom gets +0%
The player in the middle gets +10% etc...
Ranked plays gives a flat 2x multiplier to the base rate
So the 'average' player who wins/loses 50/50 and comes middle of the table will be getting +30% bonus (additive +20% for winning/losing and +10% for getting middling XP) to the base rate on average, bringing the earning rate to 15.6/min. A player who wins and comes top of the server, will be getting 18/min. Translate that to Ranked play and it becomes 31.2/min on average and 36/min at peak.

Credit Booster Breakdown

Ever curious about how many Credit you can earn from Credit Boosters? Here is a brakdown for both Casual and Ranked play.

In Casual play:
3-hour booster will give you 2,808 extra credits on average (3,240 at max)
6-hour booster will give you 5,616 extra credits on average (6,480 at max)
12-hour booster will give you 11,232 extra credits on average (12,960 at max)
18-hour booster will give you 16,848 extra credits on average (19,440 at max)
In Ranked play:
3-hour booster will give you 5,616 extra credits on average (6,480 at max)
6-hour booster will give you 11,232 extra credits on average (12,960 at max)
12-hour booster will give you 22,464 extra credits on average (25,920 at max)
18-hour booster will give you 33,696 extra credits on average (38,880 at max)

Match Size Penalty

This system has been around since the start, it simply hasn't been properly shown in-game yet and that's something we need to fix before we officially release.

The 'Match Size' penalty is intended to prevent players from farming in small groups and kicking players who join in. It's only for less than 10 players, and it works by modifying the base rate for the duration that the server is below that number:
8-9 players = base rate of 10/min (-2)
6-7 players = base rate of 8/min (-4)
4-5 player = base rate of 6/min (-6)
2-3 player = base rate of 4/min (-8)
1 player = base rate of 2/min (-10)
There's also a 'Team Imbalance' to try and get players to swap to the smaller team. The penalty for the larger team there is:
A team with +2 players gets 11/min (-1)
A team with +3 players gets 10/min (-2)
A team with +4 players gets 9/min (-3)
A team with +5 players (or more) gets 8/min (-4)