By James Hibberd
January 16, 2013 at 12:00 PM EST

Will Mariah and Nicki rescue American Idol? Or are we in for another “Idol ratings dive!” headline?

Below is a chart of all the previous Idol premieres (including that funky doesn’t-really-count first season which aired during the summer of 2002). You can see why Fox shook up the panel this season. The show’s adults 18-49 premiere rating peaked in 2007 with a massive 15.8. The numbers ebbed down in ’08 and ’09. Then, in 2010, the premiere actually perked up a tick.

What caused the show to halt its decline that year? It’s impossible to know for sure, but the consensus from insiders is that media buzz surrounding the hiring of talk show host Ellen DeGeneres for the judges panel kept the ratings afloat — even though she barely appeared in the first episode (many casual Idol viewers were unaware that DeGeneres didn’t join the Idol team until after the early auditions). If that theory is correct, it’s interesting that the only judge shakeup in American Idol or The X Factor history that ever prevented a ratings decline wasn’t by hiring some high-priced diva, but a celebrity who lacked any real music industry experience.

Fox hoped Idol ratings would stabilize, but the show’s premiere had a 17 percent drop in 2011 and then an unprecedented 24 percent drop last year. What will tonight’s premiere bring?

If any new judge drives viewers to Idol this evening, it probably won’t be Carey or Minaj, despite all the headlines over their supposed feud. Granted, Minaj could help deliver eyeballs this season once we get a sample of her cutting criticism. But for the premiere, I suspect Keith Urban is best positioned to help the ratings. Country music award shows and the success of The Voice (which has country star Blake Shelton) suggest country appeal can potentially drive broadcast viewers.

One executive at a non-Fox network suspected Idol could be relatively stable tonight since last year’s big change of having X Factor run in Fox’s fall probably heavily contributed to its previous decline — so this year the Factor effect is already factored in (so to speak). Another guessed a drop around 10 percent.

So let’s make a prediction for the 12 season debut! Taking into account Idol ratings history … Fox’s weak fall performance … NBC’s The Voice being added to the fall … recent album sales of Carey, Urban and Minaj … my level of annoyance at Idol billboards in West L.A. …  the current market price of soybean futures … and the angle of the sun on my laptop keyboard at this moment … I’m going to somewhat pessimistically predict an 18 percent decline to a 6.1 rating. Thoughts?

Also, check out Annie Barrett’s 12 Wishes for Idol Season 12.

UPDATE: American Idol premiere ratings are in: Suck it, Nate Silver!

Idol Premiere History:

NIGHT 1 (+ 000) RATING
1/18/12 ..WED… 21931 7.4
1/19/11 ..WED.. 26253 9.8
1/12/10 .TUE…. 29945 11.8
1/13/09 TUE….. 30448 11.7
1/15/2008 .TUE….. 33476 13.8
1/16/2007 .TUE….. 37442 15.8
1/17/2006 .TUE….. 35531 15.3
1/18/2005 .TUE….. 33575 14.0
1/19/2004 MON…… 28964 12.9
1/21/03 .TUE….. 26502 12.4
6/11/02* .TUE….. 9852 4.8
1/19/12 …THUR… 18018 5.7
1/20/11 …THUR… 22914 7.8
1/13/10 ..WED 26416 10.1
1/14/09 ..WED…. 30343 11.8
1/16/2008 ..WED…. 30458 12.6
1/17/2007 ..WED… 36946 15.5
1/18/2006 ..WED…. 31648 13.0
1/19/2005 ..WED… 26800 11.3
1/20/2004 .TUE….. 28626 12.6
1/22/03 ..WED…. 25019 11.8

*Season 1 aired during the summer