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.

(BBC)

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