A bundle of useful info from this – The Pocket Guide to Transportation – from the U.S. Department of Transportation.
Like what governments spend on highways and transit:

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And what revenues they get from highways and transit:
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Let the interpretations begin. (Like expenditures going up for highways, revenues going down. For transit, both going up.) And look at how the feds cut transit expenditures in 2007.
UPDATE: Eric Doherty provides a comparative link for Canadian spending on transit –















Regarding federal transit spending in Canada, we see a similar drop in funding over recent years http://rabble.ca/news/2012/11/harper-clashes-transit-climate-crisis-deepends