You've probably heard that one year is equal to seven dog years . . . but that's not really accurate.   

For instance, you might know someone whose dog lived to be 17 or 18 . . . but you probably DON'T know any 119-year-old people.  So researchers at the University of Georgia came up with a more accurate way to calculate dog years.

Dogs age at different rates depending on their SIZE . . . and their aging slows down as they get older.  So here are the rules to come up with a SMALL dog's age:  

1.  The first two years of a small dog's life are each 12-and-a-half dog years. 

2.  After that, dog years are different by breed.  Each year is 4.32 dog years for dachshunds . . . 4.87 dog years for Chihuahuas . . . 5.55 dog years for cocker spaniels . . . and 7.65 dog years for French bulldogs.

3.  So an 18-year-old dachshund is really 94 in dog years . . . not 119.

Here are the rules to come up with a MEDIUM dog's age:  

1.  The first two years of a medium dog's life are each 10-and-a-half dog years. 

2.  After that, the dog years are different by breed.  Each year is 5.74 dog years for Labrador retrievers . . . 5.33 dog years for pit bulls . . . and 13.42 years for bulldogs.

And here are the rules to come up with a BIG dog's age:  

1.  The first two years of a big dog's life are each nine dog years. 

2.  After that, each year is 7.84 dog years for German Shepherds . . . and 8.90 years for boxers.

3.   So a two-year-old dachshund and a three-year-old German shepherd are both 25 in dog years.

"Tanning Mom" Patricia Krentcil is making a cameo in a gay porno flick called "Kings of New York".  And they're paying her $1,000.  Luckily for us, she won't be having sex, or even taking her clothes off.

BARBARA WALTERS is retiring next summer.  She'll announce it officially today on "The View", but she already released a statement saying, quote, "I do not want to appear on another program or climb another mountain.  I want instead to sit on a sunny field and admire the very gifted women . . . and OK, some men too . . . who will be taking my place."

Sources say LINDSAY LOHAN wants to leave Betty Ford because they took away her Adderall.  Supposedly, the clinic's doctors assessed her and decided she doesn't need it, and so she wants out.  But supposedly, her judge has said that if she pulls anymore rehab shenanigans, she's going to jail. 

Iron Man 3" topped the box office for a second week, making another $72.5 million.  "The Great Gatsby" was strong in 2nd place with a $51.1 million debut . . . while "Tyler Perry Presents Peeples" was underwhelming in 4th place with $4.9 million

CBS is NOT moving forward with the "Beverly Hills Cop" show they were working on with EDDIE MURPHY, but it could be picked up by another network.  CBS also canceled "CSI: New York" and "Rules of Engagement".  NBC has canceled "Smash", "The New Normal" and "Go On" . . . but they WILL bring back "Community".  ABC has released a teaser for their upcoming "Avengers" TV show, "Marvel's Agents of S.H.I.E.L.D.".  The network also picked up a sitcom starring REBEL WILSON . . . and canceled "Happy Endings" and "Body of Proof".

It's official:  SETH MEYERS from "Saturday Night Live" will take over for JIMMY FALLON on "Late Night" next year . . . after Fallon moves to "The Tonight Show".  Seth will remain on "SNL" through this fall, until he leaves in January to begin preparing for "Late Night"

Lately it's been looking a lot like SELENA GOMEZ is back with JUSTIN BIEBER.  But maybe that's not true.  In a recent radio interview, Selena was asked if she's, quote, "Completely available in every way."  And she said yes.  Twice.  Meanwhile, JUSTIN BIEBER posted a picture of himself and a friend drinking beer.  Now, Justin is 19 years old . . . but the picture was taken in South Africa, where he's currently on tour, and where the drinking age is 18.  So it's all good. 

RANDY JACKSON will not be back on "American Idol" next season.  He released this statement:  Quote, "To put all of the speculation to the rest, after 12 years of judging on 'Idol' I have decided it is time to leave after this season."  There's talk that NONE of the current judges will be asked back. 

E! Online says that Fox is bringing back "24" for a limited run, and KIEFER SUTHERLAND will be back.  Fox actually won't confirm it, but so-called "sources" say it's a done deal.  "24" ran for eight seasons before finishing its run in 2010.  Plans for a movie were scrapped last year

MANTI TE'O'S fake girlfriend made the "Maxim" Hot 100, at #69.  The top five ladies are Miley Cyrus, Selena Gomez, Rihanna, Mila Kunis and Jennifer Lawrence.  "Today" show host HODA KOTB was a surprise entrant, at #79. 

Yesterday on the "Today" show, MARTHA STEWART met her two online suitors.  One was a filmmaker named Stan, and the other was an "international steel trade executive" named Larry.  Martha will go out with both of them, and MATT LAUER will provide updates on "Today".

The "Great Gatsby" remake with Leonardo DiCaprio hits theaters this weekend, along with a new comedy from Tyler Perry called "Peeples" that stars "Scandal's" Kerry Washington and is sort of like "Meet the Parents"