The document discusses trends in US labor force participation rates from the 1960s to the present. It notes that participation increased steadily for both men and women until the 1990s, when growth began to decline. The peak participation rate was in 2000 at 67.3%. By 2005, the rate had fallen 1.5% and there has been a continuous slow decline since then. A key factor is the retirement of Baby Boomers, which is expected to further lessen the size of the labor pool going forward as the population ages and birth rates remain low.