The United States federal government releases data on rates of marriage and divorce in most years, along with information on the percentage of children living with two parents and single parents. Stories based on these statistics often appear in the media. Many people, however, are confused by these data–how these numbers should be interpreted and what they mean for trends in family life. The goal of this Research Brief is to help people understand how these various rates and statistics are calculated and should be interpreted. (Author abstract)