Supposed to, but doesn't. The U6 rate includes two new things: part-time workers, and a very strangely-defined category: people who are NOT working at ALL, AND were looking for work previously, AND have stopped looking for 4+ weeks.

It doesn't capture the common on-the-street definition of the word "underemployment", such as a tech worker flipping burgers at mcdonald's.

Perhaps that category is simply to hard or expensive to measure, or it's specifically being avoided. Either/or really.

the only signal I can think of is returns on student debt to measure "employment quality" - i.e how well is my education capital being deployed, but any realistic evaluation of the labor market will be complex and include qualitative data.

Seems like its studied and there are many types of underemployment and they each have difference causes. Its probably tracked somewhere by economists.

https://en.wikipedia.org/wiki/Underemployment

[delayed]