Are you really jumping to that conclusion from a single number? Not only that, are you saying that reduced work effort leads to reduced productive output?
If I follow your logic, and what the study showed, if I start working at 16, but you go to university, and get a masters degree so do not the start work until you're 25, I have put in more work effort, and you are now making us all poorer.
If I follow your logic, and what the study showed, if I start working at 16, but you go to university, and get a masters degree so do not the start work until you're 25, I have put in more work effort, and you are now making us all poorer.