Almost every twentieth boy's first name in the USA begins with the letter R…
This makes the initial R a great deal more common than average: As there's 26 letters in the alphabet, each letter appears as an initial in about 3.8 % of all boys' first names. However, 3.8 % is just the average. Of course, the initials of boys' first names aren’t that evenly distributed, with some letters being rarer than others. In the US, the initials J and A are particularly frequent for boys' first names, while very few names begin with the letters U and X.