Anyone who’s paid a traffic ticket in D.C. knows their money is helping out the District government. But an analysis released today shows the extent to which D.C. relies on such “nontax revenue,” meaning money from fees and fines, is bigger than they might expect.

District, Measured—the data-based blog of D.C.’s Office of Revenue Analysis—finds that in 2014, nontax revenue (which also includes charges for services like inspections, records requests, and ambulances) comprised 13 percent of D.C.’s general fund. The general fund comprises every dollar the local government can appropriate and use besides what goes into special funds.

“We found that collections from emergency ambulance fees, traffic fines, and building permits were the leaders [of nontax revenue sources,] each growing an average rate of 17 percent, 8.2 percent, and eight percent respectively,” Seble Tibebu, an analyst for the Office of the Chief Financial Officer, writes. “Traffic related fines however consistently topped the list during the past ten years, [fiscal years] 2005 [through] 2014.”

In those ten years, D.C.’s nontax revenue increased 27 percent—from about $735 million in 2005 to about $936 million in 2014. But growth of D.C.’s general fund matched pace: nontax revenue consistently made up 13 to 16 percent of the general fund in that period. According to an OCFO report released last month, D.C.’s general fund revenue in fiscal year 2014 was $7.07 billion; taxes (including dedicated taxes) contributed 86.7 percent of that amount.

The ORA says the District’s “unique character” may be behind why D.C.’s general fund has a greater share of fines and fees than those in nearby jurisdictions do.

Graphs and tables via D.C. Office of Revenue Analysis.