If you're serving burgers and Bud Light at your backyard wedding, don't worry. You and your spouse may have the last laugh.

A new study found that couples who spend less on their wedding tend to have longer-lasting marriages than those who splurge. The study, by two economics professors at Emory University, found a similar correlation between less-expensive engagement rings and lower divorce rates.

The study's authors didn't examine why, although they floated a few theories.

"It could be that the type of couples who have a ... (cheap wedding) are the type that are a perfect match for each other," said Professor Hugo M. Mialon, who co-authored the study with Andrew M. Francis.

"Or it could be that having an inexpensive wedding relieves young couples of financial burdens that may strain their marriage," he said.

The research was based on a detailed survey completed by 3,151 adults in the United States who are, or have been, married. The authors believe theirs is the first academic study to examine the correlation between wedding expenses and the length of marriages.

Specifically, the study found that women whose wedding cost more than $20,000 divorced at a rate roughly 1.6 times higher than women whose wedding cost between $5,000 and $10,000. And couples who spent $1,000 or less on their big day had a lower than average rate of divorce.

The study won't be cheered by the booming wedding industry, which encourages couples to spend freely on everything from invitations and flowers to videographers and Champagne. Couples in the United States spent an average of $29,858 for their big day in 2013 -- a record high -- according to a survey of 13,000 brides and grooms by wedding website TheKnot.com.

"The wedding industry has long associated lavish weddings with longer-lasting marriages. Industry advertising has fueled norms that create the impression that spending large amounts on the wedding is a signal of commitment or is necessary for a marriage to be successful," Francis told CNN in an e-mail.

"Overall, our findings provide little evidence to support the validity of the wedding industry's general message that connects expensive weddings with positive marital outcomes," he said.

Planning a wedding? In addition to slashing costs, you might want to invite those extra co-workers and far-flung cousins, too. The Emory study also found that the greater the number of people who attend a wedding, the lower the rate of divorce.

"This could be evidence of a community effect, i.e., having more support from friends and family may help the couple to get through the challenges of marriage," Francis said. "Or this could be that the type of couples who have a lot of friends and family are also the type that tend not to divorce as much."