70 percent of the population is on Facebook, and when you figure in the older people 80 or 90 that don't bother with it, and the homeless people, or people who can't afford a phone, you have a small number left. There is a big chance, for example, someone who is like 49 years old and not on Facebook, that they could most likely be a sex offender, as they aren't permitted to be on Facebook or something is just wrong with them socially or mentally or they don't want to be found. Very few people in that age range just choose not to be on Facebook. Most likely there is a reason. So next time someone in that age range says they don't do Facebook, be skeptical of them. There all ways is the chance their normal and choose just not to, but that is a very small chance .