The official unemployment rate calculated by the Bureau of Labor Statistics excludes people who have not actively sought a job in the preceding four weeks, as they are no longer considered part of the civilian labor force." - from this article
How does that work? You still need money to survive but you’ve given up looking for work? You can’t be on welfare forever - how do those folks survive?
People who take jobs under the table, people who go back to school full-time, people who live with parents, people who are stay-at-home parents… the list goes on.