The Myth of 9 to 5

"[W]hy is 9 to 5 to commonly used to describe a typical work day? Nationwide, about two-thirds of full-time wage and salary workers start their days between 6:30 and 9:29 a.m., according to Bureau of Labor statistics, but the greatest concentration get to work between 7:30 and 8:39. Quitting time for more than half of these workers was just as varied. They leave between 3:30 and 6:29 p.m., with the greatest concentration heading home between 4:30 and 5:29."