The old adage used to be that one year is equal to seven dog years.

Researchers at the University of Georgia are about to tear a hole in that universe.

It's a little confusing, so I'm going to do my best to translate. The gist of it is that small dogs age faster than medium or big dogs until they're two years old. Then big dogs age faster.

Here are the rules they came up with:

SMALL DOGS:

  • The first two years of a small dog's life are each 12.5 dog years.
  • After that, each additional year varies by breed:
    • Dachshunds -- 4.32 years
    • Chihuahuas -- 4.87 years
    • Cocker Spaniels -- 5.55 years
    • French Bulldogs -- 7.65 years

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

MEDIUM DOGS:

  • The first two years of a medium dog's life are each 10.5 dog years.
  • After that, each additional year varies by breed:
    • Labradors -- 5.74 years
    • Pit Bulls -- 5.33 years
    • Bulldogs -- 13.42 years

(So, this means my idiot, almost-2-year-old DJ is almost 21. Go figure.)

LARGE DOGS:

  • The first two years of a big dog's life are each nine in dog years.
  • After that, each additional year varies by breed:
    • German Shepherds -- 7.84 years
    • Boxers -- 8.9 years

(So, this means a 2-year-old dachshund and a 3-year-old German shepherd are both 25 in dog years.)