Rate of Change in Baby Names Over Time

October 05, 2021

Anakin, Riggs, Lucifer? It seems that people are naming their kids crazy things nowadays. But the skeptic in me wonders if maybe this has always been the case. Names that are new today seem strange and weird, but after a few decades they become normal. Let's take a look at the data to see if baby names really are changing faster than before.

The more I learn about names, the more I learn that many names which seem traditional are anything but. Take, for example, the name Gary. Growing up in the United States in the later part of the 20th century, this seemed like a completely normal, traditional, and even boring name. But it wasn't always this way. In fact, the first name Gary sprang from practically nowhere in 1926. That was the year that actor Frank Cooper changed his stage name to Gary Cooper, in honor of his agent's hometown of Gary, Indiana. You can see the pretty obvious results of this decision here:

Previous trends aside, it really does seem that baby names are changing more quickly nowadays. Anyone who is a fan of the NBA will recognize many once-unfamiliar names such as Kobe, Shaquille, and Jalen. Meanwhile, other parents are turning to Disney for inspiration, naming their children things like Ariel and Nala.

When all else fails, it's time to look at the data. We examined data provided by the U.S. Social Security Administration to compute the rate of change in baby names from year to year.

• A score of 0 means the names were exactly the same as the year before
• A score of 100 means that all of the names changed

Are names really changing faster now than before? Let's see:

There's a few interesting things about this chart.

1. Names are changing faster now then they used to, but the difference isn't that extreme.
2. Names in the U.S. started to "liberalize" during the 1960s, perhaps mirroring changes that were happening in society at large.
3. As expected, names for girls change faster than names for boys. Many people have noticed this phenomenon and speculate that people want their boys to have "solid" names and their girls "light and whimsical" names.
4. What's surprising to me is the large reduction in the rate of change that happened to girl's names in the 2010s. I have no convincing explanation for why this might have happened.

100 Years of Change

Small changes every year add up to some pretty big changes over the course of a century. It's true that some names, like John and Elizabeth, have remained common for hundreds of years. But other names, like Gary or Judy, spring up suddenly and then almost totally disappear. Over a hundred years, the changes become quite large. Between 1920–2020 the total change in American baby names was 78.9% for male names, and 81.6% for female names.

A Very British Surprise

Many people would expect American baby names to change quickly. After all, America is a very "individualistic" country which doesn't value traditional as highly as other countries. On the other hand, I would expect the United Kingdom to have much less turnover in their baby names from year to year. So do they?

I was able to obtain some comprehensive baby name data for England and Wales for the period of 1996–2016. I charted how baby names in England changed relative to those of the United States. My assumptions were incorrect. Baby names in England are actually changing more quickly than those of the United States.

I don't have a great explanation for why this might be either. My first instinct is that perhaps immigrants in the United Kingdom are less assimilated than those in the United States. But I'm not sure this can explain such a large rate of change in baby names. Annual immigration to the UK is only about 0.5% of the population, but British names are changing at a rate of nearly 9% annually. Let me know in the comments if you have any ideas for why this might be happening.