First comes love, then comes marriage. Or at least that’s how it used to go.

According to a new Pew study, a record number of adults older than 25 have yet to be married, and by the year 2030 a quarter of those between age 25 and 34 never will have walked down the aisle.

NBC’s Tom Costello headed to Washington, D.C., to find out just why young adults are postponing trips to the chapel.

Many of those he interviewed cited the high cost of living and significant student loan debt after leaving college. One, though, questioned the need to get married when “50 percent” of marriages end in divorce.

However, a variety of factors — cohabitation before marriage, having a child out of wedlock, and education — influence marital status.

The Heritage Foundation’s Index of Culture and Opportunity noted that since the 1960s, the marriage rate has decreased by roughly 50 percent. Such a sharp drop, writes W. Bradford Wilcox, director of the National Marriage Project, can be attributed to shifts in public policy, the economy and culture.

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