Have you visited the program HowManyOfMe.com? It allows you to enter any name and instantly see how many of the 309 million people in the United States share that name. It says that there is only one #mark kupferman in the United States. It is based on statistical data from the US Census Bureau, so it must be right.
For example, when I enter my name it tells me that there are 1,459,093 people with the first name of “Mark.” And there are 303 people with the last name of “Kupferman.” When it puts the two together, it turns out that there is only one Mark Kupferman in all of the United States.
The site also features some interesting stats about the most popular last names (Smith, Johnson, and Williams); the most common boy names (James, John, and Robert); the most common girl names (Mary, Patricia, and Linda) as well as an interesting list of the most searched famous people (Harry Potter, George Bush, and James Bond). Incidentally, there are a total of 102 people in the US with the name “Harry Potter.”