From the Random Facts website: “The probability of a first marriage ending in a divorce within 5 years is 20%, but the probability of a premarital cohabitation breaking up within 5 years is 49%. After 10 years, the probability of a first marriage ending is 33%, compared with 62% for cohabitations.” (Harrar, Sari and Rita DeMaria. 2007. The 7 Stages of Marriage: Laughter, Intimacy, and Passion. Pleasantville, NY: Reader’s Digest Books.)