A new idea has emerged to help bail the Metropolitan Transportation Authority out of its financial mess: impose a 50 cent tax on every ride by car services in the city, including those booked though the hugely popular Uber app. NY1's Jose Martinez filed this report.

It's a tax on every cab ride in the city—50 cents—directly to the Metropolitan Transportation Authority. It's listed right there on the receipt.

All those rides add up, generating close $90 million last year for the cash-strapped transit agency, but it's not imposed on livery car and limousine services—including Uber, the app-based, ride-hailing service that's booming in popularity. 

"They have no MTA trip-tax requirement. If they did, that would probably bring in about $70 million annually. And this is a time where I think we're all extremely conscious of the need for support for the MTA infrastructure," says Taxi and Limousine Commissioner Meera Joshi.

The city's Taxi and Limousine Commission and an East Harlem Assemblyman say its time to extend the 50-cent surcharge beyond green and yellow taxis—not just because the MTA needs money—but because car service ridership is exploding, with close to 400,000 people using the for-hire vehicles each day.

"This is an opportunity for us to raise additional revenue for the MTA by putting the 50 cent surcharge on all for-hire vehicles - this includes Uber, Lyft, as well as the folks who currently are not paying the MTA surcharge," says Assemblyman Robert Rodriguez.

The idea, which has been pushed by Daily News editorials, is one of several transit-funding proposals being kicked around as the MTA struggles to fill a $14 billion shortfall in its Capital Program to maintain and expand the system.

As with the all the other funding proposals, the MTA isn't publicly standing behind this one, but an agency spokesman says the MTA does welcome any and all ideas on how to better bankroll the transit system.

The proposal comes as the car service industry has expanded by 55 percent since 2011, largely fueled by Uber's popularity.

Uber already pays a sales tax that's not dedicated to mass transit. A spokesman says the company would be willing to have that sizable sum go to the MTA without adding the 50-cent surcharge.

With the taxi industry in a state of upheavel, the rules may end up getting rewritten again.