I think you can say that the amount of salt has gone down. I don't think you can conclude from that alone that there has been progress. As was said earlier, it depends on weather. Also, at a conference here in Ottawa last spring they talked about the effects of global warming and what it would do to winter maintenance activities; the conclusion was that it would mean more salt would have to be used.
On November 27th, 2006. See this statement in context.