Using a list of the 52,131 active medallion taxi drivers in New York City, I’ve graphed the frequencies of the 20 most common first and last names. Middle names were not considered. I did not bin alternate spellings of the same name. As such, the five most common first names are Md, Mohammad, Mohammed, Muhammad, and Mohamed.

The heat map below the bar graphs shows the frequency of first and last name pairings. This hints at the diversity of first or last names in some countries compared to others. For example, Singh is the most common last name, but none of the most common first names are paired with it; it is traditionally a last name in India, but due to the diversity of first names in India, none of them are in the top 20. The most common first name paired with Singh is Balwinder, which is the 52nd most common first name. Conversely, Jean (the French version of John) is the sixth most common first name, but is not associated with any of the top 20 last names. Francois, the most common last name paired with Jean, is not even among the 100 most common last names.

Data source: https://data.cityofnewyork.us/Transportation/Medallion-Drivers-Active/jb3k-j3gp