An article in the Toronto Globe and Mail newspaper notes that traffic jams in Canada's nine largest cities are estimated to "[cost] the economy as much as $3.7-billion a year in delays, wasted fuel and greenhouse gas emissions."
Now, that's a lot of money, but consider that, as of the most recent census (2001), combined population of Canada's nine largest cities comes out to 8,722,246 - or, a bit more than the population of New York City (8,085,742). [The largest city in Canada had a population of 2,481,494; the ninth-largest (Quebec City) had a population of 507,986. That would make Quebec City the 32nd largest city in the US (based on 2003 population figures), after Tucson, AZ.]
In other words, assuming that Canadians and Americans have similar habits, if Canada is losing $3.7B a year in traffic jams, NYC alone is losing about as much (indeed, having spent considerable time in NYC and in Canada's three largest cities, I'd bet the Big Apple loses twice as much). The amount the US as a whole must be losing each year boggles the mind - enough to buy Google Corp and have some cash left over for frappucinos.
I think these numbers underscore the importance of the ITS industry's efforts. Incremental benefits from ITS can save huge dollars, not to mention the reduction in stress and frustration for individuals.