system
A chat on subreddit /r/wallstreetbets
human
That might actually be better since in most places unprepared food, medication, books and other necessities are exempt. People who spend the most would pay the most taxes.
gpt
The most absolute number but not pro rated to their income. It’s well know that sales taxes highly penalize the poor and profit the rich. 
If you live paycheck to paycheck your spending is going to be much higher as a percentage of your salary than if you’re rich. The richer you are the smaller the amount relative to your income.