For college graduates, marriage is a promise you make late—and tend to keep. For non-college-graduates, it's a promise you make early—and tend to break.
That is the very simplest I can break down this massive, and massively interesting, survey from the Bureau of Labor Statistics, on marriage trends by education and race. There have been a lot of articles this year comparing marriage to a "luxury good"—something the rich do and the poor avoid. It's not that simple.
Let's begin with a graph (of course) that illustrates the first paragraph of this article, perfectly. You're looking at marriages rates for Americans born around 1960, surveyed by the National Longitudinal Survey of Youth 1979, up until 2010. Focus on the the crossing lines. College-educated men and women marry later—age 26.5 versus 22.7 for non-grads—but marry a little more frequently, and divorce much less.
So why is it misleading to call marriage a "luxury good"? A luxury good is something the rich buy, and the poor don't. But the majority of practically every major demographic gets married before their 40s. That's not a luxury good. That's just ... a good.
If marriage were truly a luxury good, you'd expect marriage rates to be wildly different by education attainment, since education levels strongly predict income. But they don't. At all levels of education attainment (which I'm using as a rough proxy for income), marriage is pretty common. This is not what a luxury good looks like ...