Germans with vocational training, as compared to general education, lose their employment edge over time, his research shows. By age 50, former apprentices begin leaving the labor market.

Some believe a workforce with narrow skills and problems adapting to change explains slower growth in Europe, compared to the U.S., Hanushek writes.

The limited existing apprenticeships in the U.S. have been most successful in the building trades, in large part because of their unionized and regulated employment. Indeed, in many people’s minds discussion of apprenticeships leads to images of the neighborhood plumber or electrician who is paid high wages for ever-needed services. If currently unskilled youth could be provided training in these areas, there could be obvious employment gains. But, such trades are a small portion of the available unfilled jobs.

The larger skill gaps are found in a wide range of service and technology areas, many in the white-collar occupations.

Poorly educated youths will have trouble learned skilled occupations, writes Hanushek. Job training can’t  substitute for “high-quality primary and secondary schooling that provides basic cognitive skills to all and prepares them for an uncertain future.”