This declining contribution is mainly due to a trend toward lower birth rates. In the early 1950s, there were about 24 births per 1,000 people in the United States. The general view about the fall in labor force participation rates is that discouraged workers are leaving the labor force. Labor is calculated as the fraction of the working population multiplied by the general population.
So how could it fall when the economy was booming and the labor force participation rates of the working-age population were growing in all age categories? The participation rate in the civilian labor force is the sum of all people employed or considered officially unemployed divided by the total population over 16 years of age. On the other hand, young people (whose participation in school and not in the labor market has reduced the aggregate LFPR for decades) are exceeding (this is true for men) or are close to exceeding (it is true for women) their pre-pandemic LFPR. This suggests that younger and older workers do not face unique challenges in the labor market on an ongoing basis. Because older Americans are less likely than younger Americans to be part of the workforce, this demographic shift reduced the overall labor force participation rate.
In fact, small changes in these enormous flows largely determine whether the labor force participation of prime age workers increases or decreases. The problem is that population demographics have changed in recent years in a way that will reduce labor force participation rates. Only one state (Utah) and the District of Columbia experienced increases in their labor force participation rates for the total working-age population aged 16 and over, while 38 states experienced decreases. Since labor market demand is much higher than before the pandemic, this is surprising and indicates a worrying level of discouragement among the unemployed.