How many shy people are in the world?

Depending on the source, and how you interpret what it says, 20-40 per cent of the world population is shy. I say it depends on the source and the interpretation because western cultures simply don't understand what "shyness" is. It's very difficult to explain, but shyness in and of itself is not a trait-- it's a symptom of a trait that [western] psychology has all but ignored; SPS, or Sensory Processing Sensitivity. The first person to do any notable research, starting in the 1990's, is Dr. Elaine Aron, author of the book, "The Highly Sensitive Person." google her name or the name of the book and you'll find her/it.