Worth noting: article is from 2014. It's unfair to ask it to cite trends that started after the date of publication (and likely after the finalization of the research, which probably dates closer to 2012, the cited end date in the article).
Ah! I've been so spoiled by the moderation on HN that when I see an article that doesn't have e.g. (2014) in the title, I assume it's recent! You're absolutely right.
