I want to know the answer to the following question:
What is the main source of income for Paris?
All the background I'm provided with is that "The largest part of the budget (38 percent) went for public housing and urbanism projects; 15 percent for roads and transport; 8 percent for schools (which are mostly financed by the state budget); 5 percent for parks and gardens; and 4 percent for culture.". Is that enough to answer the question?