So if you spend your time switching a lot, then the evidence suggests you will be slower, you'll make more mistakes, you'll be less creative, and you'll remember less of what you do. I wanted to know: How often are most of us engaging in switching like this? Professor Gloria Mark, at the Department of Informatics at the University of California, Irvine, who I interviewed, has discovered that the average American worker is distracted roughly once every three minutes. Several other studies have shown a large chunk of Americans are almost constantly being interrupted and switching between tasks. The average office worker now spends 40 percent of their work time wrongly believing they are "multitasking"-which means they are incurring all these costs for their attention and focus. In fact, uninterrupted time is becoming rare. One study found that most of us working in offices never get a whole hour uninterrupted in a normal day.

— Stolen Focus by Johann Hari (Page 41)