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The Distribution of Users’ Computer Skills: Worse Than You Think (2016)
(www.nngroup.com)
This is a most excellent place for technology news and articles.
Eh, I used to use those back in the day, but for the last decade or so I've been using mostly concentrated spite and it seems to work just fine (though I can't wait for the AI bros to invent a computer that can feel pain... now that'll make computer wrangling fun again!).