Wish you were a little bit taller? Imagine if you were born a century ago. New research has revealed how much heights have changed over the last century. Enter your information into the calculator below, which is based on 100 years of height data from 187 countries, to see how tall (or, likely, how short) you would have been if you’d been born at the beginning of World War I. Compared to growth trends in other countries, Americans are getting shorter of late.