A rare sight among millennials. (Flickr user micadew under CC license)

Millennials are poised to become the nation's largest living generation this year. As they grow as a percentage of the population, more of them will reach the age at which Americans historically have gotten married. And many baby-boomer parents are probably eagerly anticipating the big day when their son or daughter walks down the aisle (and the grandkids that will follow.)

But, according to new research, millennials are not showing many signs of interest in getting hitched as they get older, and, as a result, the marriage rate is expected to fall by next year to its lowest level to date.

That is a finding by Demographic Intelligence, a forecasting firm with a strong track record. “Millennials are such a big generation, we’re going to have more people of prime marriage age in the next five years than we’ve had at any time in U.S. history. For that alone, we’d expect an uptick in marriage rates,” said Sam Sturgeon, president of Demographic Intelligence. “That’s not happening.”

In the firm's new U.S. Wedding Forecast, compiled from demographic data, Google searches and a host of other variables, Sturgeon projects that by 2016, the marriage rate will fall to 6.7 per 1,000 people, a historic low. That includes people getting married for the second or third time.

In 1867, the first year for which national marriage statistics were recorded, the marriage rate was 9.6 per 1,000 Americans. It peaked in 1946 at 16.4 per 1,000 as men were returning from World War II, and it bounced around from 8.5 in 1960 to a high of 10.8 in the mid-1980s. Starting in the 1990s, it began a long and, in the 1990s, precipitous drop.


Source: Pew Research Center

In fact, in 1984, when baby boomers were at prime marrying age, a total of 2.48 million marriages were recorded, the highest number the country had seen. In 2013, the most recent year for which there is data, the number of marriages had dropped to 2.13 million.

“We won’t get anywhere close to that high number of marriages again,” Sturgeon said.

Demographers cite several reasons reason for the  massive generational shift in marriage trends.

1) Millennials continue to delay marriage because of economics, education and preference. In 1960, fewer than 8 percent of women and 13 percent of men married for the first time at age 30 or older, University of Maryland sociologist Philip Cohen has calculated. Now, nearly one-third of women and more than 40 percent of men who marry for the first time are 30 or older.

Cohen, who has tracked falling marriage rates around the world, has projected that, if the current pattern continues, the marriage rate will hit zero in 2042.

2) The United States continues to become more secular and less religious. The Pew Research Center reported recently that the share of Americans who describe themselves as Christians dropped from 78 percent to 71 percent between 2007 and 2014, while the number of atheists, agnostics or those of no faith grew from 16 percent to 23 percent.

[Related: Christianity faces sharp decline as Americans are becoming even less affiliated with religion]

3) Millennials have alternatives. In the past, living together or having children “out of wedlock” was met with severe social stigma, but no longer. Cohabitation rates are on the rise — 48 percent of women interviewed between 2006 and 2010 for the National Survey of Family Growth cohabitated with a partner as a first union, compared with 34 percent in 1995.

Births to unmarried women also are on the rise. Forty-one percent of all births are now to unmarried women, 2.5 times as high as was reported in 1980 and 19 times as high as in 1940.

“Marriage is, in some ways, in the worst place it’s ever been,” said W. Bradford Wilcox, a sociologist at the University of Virginia, director of the National Marriage Project and founder of Demographic Intelligence. “I don’t think we’re ever going to see a major upswing. But we may have reached a plateau. The numbers suggest we may be touching bottom.”

Hopeful signs, Wilcox said, are rising rates of marriage among the educated. The U.S. Wedding Report notes that weddings for college-educated women rose from 30 percent in 2008 to 36 percent in 2015. And middle-class desires for two parents to be involved in the lives of children bode well for stable marriages, he said.

In addition, the growth of the Hispanic population should propel the percentage of Hispanic brides from 15 percent in 2008 to 18 percent this year, according to Demographic Intelligence.

Monitoring the Future, an ongoing survey of youths, further reports that 80 percent of female high school seniors and 72 percent of males in 2006 to 2010 said marriage and family are “extremely important” to them — numbers that have remained consistent since the mid-1970s.

Source: Monitoring the Future
Source: Monitoring the Future

That shows a strong marriage norm in the United States, Sturgeon said. But whether millennials will follow it is anyone's guess. "We kind of hope we've reached a floor," he said, "but we really aren't sure."

Brit Bertino, a wedding planner in Las Vegas and vice president of the Wedding Industry Professionals Association, is seeing the trends firsthand. Despite record tourism in the past year, and Las Vegas's reputation as the “Wedding Capital of the World,” the number of marriage licenses issued there has dropped nearly 40 percent in the past decade.

“My business is definitely down. I’m seeing a 50 percent drop just from last year,” Bertino said. “Las Vegas is definitely hurting.”

But Bertino also understands why. At 31, she, is a millennial, too. And though she’s in the wedding business and said she would like to marry someday, she is in no rush.

“I’m not very traditional, so I wouldn’t mind having a child before marriage,” she said. “Like a lot of people, I’m holding off on marriage until I’m sure I’ve found the right person.”

Update: In an e-mail after this story was published, Bertino said the company's revenue is actually not down 50 percent. "Our forecasted overall revenue remains the same since last year due to the larger scale of weddings produced from our offices," Bertino wrote.