Everyone knows that air pollution, with all the new cars on the road, is getting worse and worse, right?  Well, not exactly, at least according to new EPA data which show that levels of air pollution in our major cities continue to improve.  Indeed, 2004 had the lowest ozone smog levels since states began measuring it back in the 70s. Based on preliminary data from around the country, days exceeding EPA’s tough new 8-hour ozone standard declined an average of about 50 percent below 2003, which was itself a record year.  With major cities like Los Angeles, Denver, and Phoenix experiencing sharp declines in smog, it seems we can all breathe easier with this new air pollution data.