I remember being a kid and being able to scam my way into not going to school by the simple fact that if I woke up once the heard the heater kick in, and ran to the bathroom, I could sit on the toilet which was right next to the heat vent, put my head next to it, heat up my forehead and after 2 minutes of heat, run right upstairs, have my mom put her hand on my forehead and say,
"Oh, you have a fever. Better stay home."
The truth is that less than 10% of the "sick days" I had during school were genuine, and the same percentage of days I presume hold true in the adult working world. Since leaving home I have only had 1 sick day and that was when I had food poisoning. Beyond that I've gone to work sick, tired, perhaps a little hung over, but only once in 15 years did I ever take a sick day. Ergo, the following chart isn't a measure of relative healthy, but relative propensity to lie.