Streetcar and LRT can mean different things though. If it has it's own ROW, I generally consider it LRT. I'm sure you'd know better, though.
http://en.wikipedia.org/wiki/Light_rail_in_North_America#Usage_of_light_rail_in_North_America
This one shows LRT in Boston at 267K and Calgary at 271K. Surprising. I always thought Toronto and Calgary battled it up for #1 in Can./USA.
http://en.wikipedia.org/wiki/List_of_North_American_light_rail_systems_by_ridership