Bus rapid transit system could boost metro Detroit, experts say

[Jason]

Population x per capita income, for each of the 4 RTA counties, added together.

That's the total amount of income in the RTA area, so if income were taxed at 100% that's how much money you would collect.

You only need to tax a fraction of a percent to get enough money to build the entire system from scratch immediately.

Edit: Yeah mwilbert that's what I meant, you beat me to it. I just used the population and per capita income stats on wikipedia to come up with that number. It's not a perfect number since not all income is taxable, but like you said it's in the ballpark.