I don't know the number. It will differ in different kinds of neighbourhoods. If you're in a highly dense mixed-use neighbourhood in Toronto itself, you'll likely make that trip to the transit service. If you're in a lower density environment--in a rural environment, for example--you're less likely to make that trip to the transit service. It also depends upon the kind of urban form you have in the area.
On November 2nd, 2011. See this statement in context.