What's Your Number Baby: Order your unique world population gift certificate. PDF: Download your PDF certificate to print at home. Perfect for: A unique and unusual gift idea for new babies or loved ones. Discover: You and your family are all part of the biggest population expansion since time began - discover what number in our 7 billion-plus population you are! Population: Shows what number you are in the world's current population! World events: Most certificates show world events from the year you were born. What's Your Number Baby Birth Certificate | Living Social