This is of particular interest to me for two reasons. First, because generational identities like "millennial" are largely made-up marketing gimmicks. And, second, because the innate earnestness of many "millennials" makes it that much more fun to tease them. (Editor's note: Philip is old.)
Curious about how this trend looked over the long term, I reached out to the author of the Pew report, Richard Fry, and he very generously provided annual data back to 1968. That allowed me to compare the millennial generation to Baby Boomers (which is an actual defined generation), what is often called the Silent generation (the Boomers' parents) and Generation X, the cool generation of cool people. (Editor's note: That's debatable.)
From 2008 until 2011, the percentage of people aged 18 to 34 who lived outside the home slipped downward rather dramatically. The same thing happened between 1981 and 1983, another period during which the country was in a recession.
What's interesting is what else happened from 2008 to 2011 that didn't happen from 1981 to 1983: The generation that composed most of the 18-to-34-year-old population shifted from one to the next. (To the extent that generations exist, etc. etc. etc.)
In 1968, most 18-to-34-year-olds were from the Silent generation. In 1980, most were Boomers. In 1999, most were Gen X. Now, most are millennial. And they're more likely to live at home than their parents, grandparents and great-grandparents.
Why? Fry explores this question, but isn't able to narrow down an answers. (No, it isn't student debt, for example, because the same trend affects those who didn't go to college.)
Perhaps it is because millennials are little babies? We're going to assume it's that until we have evidence to the contrary.
(Editor's note: Philip speaks for himself and only for himself.)
(Philip's note: And his cool generation.)