CNN  — 

President Donald Trump took to Twitter Friday morning to relay a bit of good news about the labor market from one of his favorite sources on economic statistics, Fox and Friends.

The tweet appears to be referring to a Thursday release from the Bureau of Labor Statistics announcing that the unemployment rate for workers aged 16 to 24 was 9.2% in July. Many young school-aged people work during the summers when classes are on break, and that is the lowest mid-summer unemployment rate since July of 1966, according to the Labor Department data.

However, that’s not the whole story when it comes to young people and work.

The unemployment rate only measures people who are looking for employment. And over the past few decades, way fewer teens and young adults have been out in the job market.

As a percentage of the overall population, the number of people aged 16-24 who are either working or looking for work fell from a high of 69.1% in 1979 to a low of 54.1% in 2014.

It has only rebounded slightly since then, to 55.5% in July 2018.

The numbers are even lower for teens. Their labor force participation rate peaked at 59.3% in 1978, and in 2014 reached a low of 32.6%. Still, the unemployment rate for teens was 13.1% in July, which is also the lowest July rate since 1969.

There are lots of reasons behind this decline in youth employment.

One is that young people are more focused on activities that are more likely to get them into a good college, like summer internships, volunteering, camps and classes. Another is that as the rural population has declined and agriculture has become more mechanized, the original reason for summer vacation – working in the fields – has become less necessary.

Through the recession, teens and young adults faced an additional challenge: People laid off from other jobs were competing for the same positions in food service and retail that had traditionally soaked up kids who are off for the summer. As the labor market has strengthened, however, those jobs have again become more available.

Still, workforce experts have worried about the decline in youth employment because having a job at a young age is a good indicator of career success down the road.

“Learning how to function in a work environment—to be responsible, assess situations, accept feedback, identify when to seek assistance, and so on—are best learned through direct experience,” a Brookings Institution report read in 2015.

For that reason, many cities have started or beefed up summer youth employment programs to create subsidized jobs at government agencies and participating companies. It keeps kids out of trouble during the long hot months between the last and first days of school, and gives them that first line on a resume that helps land the next job, and the next.