If the labor force participation rate were still at its peak (roughly around 67%), roughly 10 million more Americans, that's the entire population of New York City plus an additional 1.5 million people, would still be in the labor force.
If the labor force participation rate were still at its peak (roughly around 67%), roughly 10 million more Americans, that's the entire population of New York City plus an additional 1.5 million people, would still be in the labor force.