According to a new study out of Emory University in Atlanta … the ideal age difference in a relationship is 12 months. Researchers found that marrying someone with only a one-year age difference to yours gives you the best chance of a successful marriage, with just 3% of people in that group likely to divorce. Not surprisingly, marriages with the biggest difference in age were the most likely to get divorced. Here's how the data broke down: Married couples with a 10-year age difference were 39% more likely to get divorced and those with a 20-year difference had a 95% chance of calling it quits. Even a smaller age difference had an effect on relationships. Couples with a five-year age gap had an 18% chance of breaking up. (Indy 100)