How do marriage market conditions affect entrance into cohabitation vs. marriage?

Widening gaps in marriage rates have received a great deal of attention in recent years, focusing on the availability of marriageable men in the local marriage market. At the same time, cohabitation has increased in prevalence, playing a role in declining marriage rates. This paper extends marriage market arguments to the formation of both cohabiting and marital unions, using contextual data at the Labor Market Area (LMA) level linked to the 1995 National Survey of Family Growth (NSFG). Findings indicate that as the sex ratio increases, the odds of marriage over either remaining single or cohabiting increases, suggesting the cohabitation and marriage are not substitutable. However, the sex ratio does little to explain black-white differences in union formation.