At Salon, Margaret Eby discusses marriage with Tara Parker-Pope, who has written a new book, "For Better: The Science of a Good Marriage." In one paragraph, Parker-Pope puts the myth of the 50% divorce rate to bed:

The 50 percent divorce rate is really a myth. The 20-year divorce rate for couples who got married in the 1980s is actually around 19 percent. Everyone thinks marriage is such a struggle and it’s shocking to hear that marriage is actually going strong today. It has to do with how you look at the statistic. If the variables were constant, then a simple equation might work to come up with the divorce rate. But a lot of things are changing. And it is true that there are groups of people who have a 50 percent divorce rate: college dropouts who marry under the age of 25, for example. Couples married in the 1970s have a 30-year divorce rate of about 47 percent. A person who got married in the 1970s had a completely different upbringing and experience in life from someone who got married in the 1990s. It's been very clear that divorce rates peaked in the 1970s and has been going down ever since.