NYT has an an article that says:
 Married couples, whose numbers have been declining for decades as a proportion of American households, have finally slipped into a minority, according to an analysis of new census figures by The New York Times.
It adds:
 The numbers by no means suggests marriage is dead or necessarily that a tipping point has been reached. The total number of married couples is higher than ever, and most Americans eventually marry. But marriage has been facing more competition. A growing number of adults are spending more of their lives single or living unmarried with partners, and the potential social and economic implications are profound.
As the society moves towards ‘global village’ and equal opportunity for women resulting in more economic independence for them, this is a natural result. All societies where women have to depend on men for economic survival have ‘strong marriage’ and where women have more independence, the marriage becomes a weaker institution.  Â