My Alternative to Prisons

I would think killing a helpless child a greater crime than killing an old man waiting to die.

Good point. Okay, starting a the age of 50 going in both directions, it multiplies as such.
If you're 50, your death would be worth $50,000, while 51 AND 49 would be $51,000. the pattern continues as such. Age 75+ the fine decreases by $1000 yearly, so a 90 year old would be $60,000.