I would like to know where I can find reliable data that lists the ratio of commuters who use public transit as opposed to other methods (automobile, bicycle, feet) for cities in Europe and North America.

The information will be used for a business/econ statistics project. I would also be interested in finding a source for comparable data of urban area density in Europe. Such information is easier to find for North America. I am attempting to predict transit use in cities with an urban area greater than one million based on the urban area population density, the population of the city, and whether the city is located in North America or Europe. In other words, I am using two quantitative variables and one qualitative variable.

I have searched around online, but have only found a few anecdotal quotes for transit use with varying methodology. I would greatly appreciate the help of anyone who can point me in the right direction to find recent data for both density and percentage public transit usage. I'm looking for all >1,000,000 cities in NA and the EU.

Admins, I apologize if this thread has been posted in an inappropriate sub-forum. Please move it at your will.

Thank you,
Agent Orange