This turn of events is fueled primarily by the dramatic drop in the share of young Americans who are choosing to settle down romantically before age 35. Dating back to 1880, the most common living arrangement among young adults has been living with a romantic partner, whether a spouse or a significant other. This type of arrangement peaked around 1960, when 62% of the nation’s 18- to 34-year-olds were living with a spouse or partner in their own household, and only one-in-five were living with their parents. 2

By 2014, 31.6% of young adults were living with a spouse or partner in their own household, below the share living in the home of their parent(s) (32.1%). Some 14% of young adults were heading up a household in which they lived alone, were a single parent or lived with one or more roommates. The remaining 22% lived in the home of another family member (such as a grandparent, in-law or sibling), a non-relative, or in group quarters (college dormitories fall into this category).