Turn based community credit system v.02

So 3 people made collaterals (same sizes), and the bank gave for them an overdraft account. Each could take 90% of 1/3 freely, but if at a moment one would take, say, 130%, the next turn he/she could only take 50%

Each turn period was determined beforehand, maybe 6 months, maybe 8 months, or else.

You'd want to use this for...