In the past 50 years, marital rates have declined significantly, especially among lower socioeconomic groups. Meanwhile increase in the ease of divorce and improvements in contracting outside of marriage (e.g.,child support laws) have made marriage increasingly similar to cohabitation, except for in the treatment of assets upon divorce. Corinne Low, together with coauthor Jeanne Lafortune, present a case that as the commitment offered by marriage declined, this division of assets offered extra "insurance" to women in high asset unions. This in turn encouraged investment in child human capital, even at the cost of one's own earnings, and allowed marriage to retain its value amongst asset holders particularly homeowners. Meanwhile, the value of marriage eroded for other groups, creating a wealth gap in marriage rates that may underly the apparent income, race, and education gap. 

Corinne Low, Assistant Professor of Business Economics and Public Poliy, The Wharton School University of Pennsylvania.