No, we don't. We need to do a better job with what we have.
The Clearest Explanation Yet for Why Millennials Are Driving Less: Shifting demographics matter, but shifting attitudes may matter more, by Eric Jaffe (City Lab)
... McDonald’s work isn’t likely to put the debate about Millennial driving habits to rest, but it does add a highly informed layer to the discussion. And her advice about what planners and cities can do while all the data points find their place—encourage alternative travel modes, and improve forecasts about driving trends—is sound regardless of the exact reasons behind the shifts.