[kbenson]

> Japanese working in large corporations just STAY late because they have to, not because they are actively working.

I think that's a distinction without relevance, depending on what you are trying to infer from the data. Plenty of people spend a portion of their paid workday not doing work either, along a wide spectrum. Some people do no active work besides fill a seat, others take no breaks beyond what is required and stay on task the entire time (sometimes there is no option to do otherwise by the nature of the work). If you're at work, you aren't able to do certain other activities you might like to do (for example, it prevents spending time with your children, even if you are allowed to recline and watch a movie while at your desk).

We can measure hours working, we can measure productivity, or we can combine them, but it's probably not useful for us to start conflating them.