Now, researchers report that the marriage rate has dropped to a new low of 31.1, meaning there are about 31 marriages in the U.S. for every 1,000 unmarried women, researchers found. In 1950, that number was 90.2. In 1920, it was 92.3.

“Marriage is no longer compulsory,” study researcher Susan Brown, co-director of the National Center for Family and Marriage Research (NCFMR) at Bowling Green State University, said in a statement. “It’s just one of an array of options. Increasingly, many couples choose to cohabit and still others prefer to remain single.”