About a month ago I read this excellent article on the fall from grace of the name ‘Hilary’. That alerted me to the fact that you can easily get US Social Security records on frequency of first names right back to the 1880s. Although Hilary focused on the raw numbers, I commented that I’d be interested in seeing the behaviour with respect to gender – specifically the tendency for ‘male’ names to become unisex or even predominantly ‘female’. Today I actually got around to crunching the data!
I found myself with 37,407 names that had been used for males, and 62,318 for females – so we immediately see that there’s a lot more diversity for female names. Of all these, 9800 are common to both genders – but only 8,564 have instances with both genders in the same year. Any such year I could use for a scatter plot of the proportion of males with a given name, out of all people with that name. So a value of 1 indicates a name was assigned only to males that year, with 0 showing that only females received it. Here’s the ratios for `Hilary’:
Proportion of male Hilarys.