For the first time in almost 100 years, more than half young adults are living with their parents in the United States. The coronavirus pandemic has closed university campuses and eliminated jobs, causing many in their 20s to move back home, according to the Pew Research Center. And the trend exceeds the number of young adults who lived with their parents during the Great Depression. How long will this last, and what does it mean for the housing market, now that 26 million adults are living with their parents?