NASCAR's national TV ratings are key.

Unlike team sports, in which venues and player uniforms aren't as drenched in corporate logos, NASCAR's action provides hours of exposure for sponsors. And unlike Major League Baseball and the NBA, which pocket viewers all week with local and regional TV games, NASCAR's weekly Sprint Cup showdowns aren't just a big piece of the TV pie; they're nearly the whole pie.

So it's noteworthy that NASCAR finished the season with its Cup ratings down nearly across the board. The breakdown:

••ABC's races averaged 3.5 percent of U.S. TV households, down 5 percent from last year and 8 percent from two years ago.

••Before that, TNT's races averaged 3.3 percent, down 8 percent from both 2008 and 2007 levels.

••Fox, which has early-season coverage, averaged 5.1 percent, down 10 percent from last year and 9 percent from 2007.

••Bucking the trend was ESPN's coverage, which was up slightly from last year but down a bit from 2007.

Sports ratings bob, tweaked by vagaries such as events being rained out or going into overtime. But for a sport known for its consistent ratings -- and one that is facing recession-related challenges to its sponsorships and attendance -- this can't be spun into anything but bad news.

Has NASCAR's TV appeal peaked? Elements that might turn ratings around include IndyCar star Danica Patrick possibly showing up on the circuit next year or NASCAR getting more Formula One drivers such as Juan Pablo Montoya, who starred this year. And while any sport wants a superstar -- such as Jimmie Johnson, who won his fourth consecutive Cup title this season -- that star gets bigger if somebody steps up to become a steady rival. See Muhammad Ali-Joe Frazier or Chris Evert-Martina Navratilova.

Next season, NASCAR will move away from its hodgepodge of starting times. Races at tracks in the Eastern and Central time zones are set to begin at 1 p.m. Eastern, West Coast races at 3 p.m. Eastern and night races at 7:30 p.m. Eastern. Consistency usually helps TV viewers develop habits, and the 1 p.m. Eastern start times might help keep NASCAR fans from wandering to NFL games in the fall.

NASCAR spokesman Ramsay Poston, who this season criticized ESPN/ ABC announcers for not being perky enough on-air, suggests teamwork can help.

''It's hard to say what effect the gang in the booth has on ratings,'' Poston said, ''but broadcasters should accentuate the positive.''

Because NASCAR is at a TV ratings crossroads.