What is the mean male adult height and standard deviation in Europe?
178cm and 7cm, respectively.


Height is normally distributed, and we know the distribution's mean and standard deviation. Therefore, we can calculate -- using a z-score table or in this case, more easily with the pnorm() function of the R statistical programming language -- the percentage of the adult male population at or below 175cm in height, the approximate maximum height (I am being conservative) for good fitment on a 16" bi-fold bike. That percentage is 33%. In other words, in a normally-distributed population with mean height 178cm and standard deviation 7cm, the percentage of people at or below 175cm in height is 33%. Put another way, one third of Europe's adult male population is no taller than 175cm. This is fundamental statistics & probability based on the established properties of the Normal distribution.



What does that look like? Here's a histogram of adult male European height, with 33% of the distribution lying at and to the left of the red line representing a height of 175cm.


What is the number of adult males in Europe?
361 million



What is, then, the number of adult males at or under 175cm in stature in Europe who could fit and ride a 16" bi-fold comfortably?
33% of 361 million or about 120 million.

The same figure for European females will be even greater due to the fact that there are more females than males and females are shorter. There is no reason to speculate, theorize and make up short-sighted BS when we can actually estimate. Hopefully, this will put to rest once and for all the self-interested, ignorant view that these bikes don't fit and are inapt for Europeans. Data talks, BS walks.