Here's why it's difficult to give a precise number:
* Definition of "Beard": What constitutes a beard? Is stubble a beard? Does a goatee count?
* Changing Trends: Beard popularity fluctuates over time.
* Cultural Differences: Beard-growing is more common in some cultures than others.
* Data Collection: There's no global organization tracking beard statistics.
Using a global male population estimate of approximately 4 billion, 55% would suggest around 2.2 billion men have some form of beard. However, remember the limitations of this calculation.