We use some names mostly for boys and some mostly for girls, but then there is a small percentage of names that, over time, switched mostly from one gender to another. Which names made the biggest switch?



It seems like a straightforward question, but it depends on how you define “biggest switch.” More on that in a bit.

I turned to our old friend: the baby names dataset from the Social Security Administration. Most citizens and residents in the United States have a Social Security number (printed on a piece of paper that you are somehow expected to keep safe from birth!), and the SSA releases a dataset of baby names annually. It provides the number of babies with a given name, split by sex and by year.

The first numbers were given in 1935, but the names in the dataset were retroactively counted pre-1935. So the data goes back to 1880. The people who were alive in 1935 were tallied by birth year. You can see the sharp increase post-1935 in the chart below.

Social Security Card Holders Counts for boys and girls stabilized around 1930. 2.5 million 2.0 1.5 Boys 1.0 Girls 0.5 0 1880 1900 1920 1940 1960 1980 2000 2018

I used this dataset to look for the names that made the biggest switch. A couple of caveats:

Not everyone in the United States has a social security number, and so this doesn’t represent all baby names every year. Only names with five or more occurrences during a given year are included, so more unique names are not in this dataset.

I don’t think either of these are an issue in this case though, because I looked for popular names that made significant shifts rather than unique names with only a few people.

Also, I limited the search to 1930 and on. The counts between boys and girls became more even around this time.

Most Basic Approach

To start, I looked for any name that switched sexes between 1930 and 2018. I defined that as any name that was at least 50 percent boys or girls and then switched majority to the opposite sex at some point. Out of the 95,137 names in the data, 2,987 switched, or about 3 percent. I quickly plotted the difference in counts over time for the 100 names with the highest counts.

Switching Between Boy and Girl There were 2,987 names that switched between 1930 and 2018. These are the 100 with the highest annual peaks. Not much to look at here. That tall 50k+ peak in the 1990s is “Ashley.” More Boys More Girls 2018 2000 1980 1960 1940 1930 10k Even 10k 20k 30k 40k 50k

This view wasn’t very useful, but at the least, you can see there’s a lot of fluctuation over time. Here’s a name-by-name view, which makes it easier to see individual trends for each name.

Switches Sorted by Greatest Span Among the names that switched, which ones grew or declined the most? Ashley Taylor Alexis Madison Tracy Kelly Joan Lauren Robin Jamie 2018 More girls 1930 Shannon Courtney Chelsea Kim Shawn Angel Jean Addison Morgan Kelsey More boys Avery Riley Harper Stacy Shelby Sydney Whitney Lynn Jaime Lindsey

By the way, these are called difference charts. They show the difference between girl and boy counts over time. It goes from 2018 to 1930, top to bottom. Turquoise means there were more girls that year, and orange means there were more boys.

Looking at the difference charts above, maybe you noticed the names — with the exception of Riley and Jaime — don’t really look like there was a switch from one sex to another. It looks more like a name wasn’t very common for one sex and then became more popular for the opposite.

Interesting. I didn’t know Ashley used to be a mostly boys name. But I wasn’t looking for names that were so-so for one sex and then popular for another.

Looking for Even Swings

I was looking for names that were equally common for both sexes, or close to it at least. So unlike my first approach, where I found the peak count for both sexes and subtracted, I calculated the ratio of the peaks. If the peak count for boys is about the same as the peak count for girls, the ratio would be close to 1.

Here are the top thirty names with a ratio closest to 1.

Looking For Actual Switches Take the ratio of peak girls to peak boys and look for the names closer to even. Ryley Landry Azariah Devyn Britt Stevie Kerry Jael Germaine Kirby 2018 More girls More boys 1930 Lorin Kenyatta Carrol Austyn Rene Kodi Brighton Sidney Charlie Casey Jules Jaedyn Shay Gentry Codi Santana Torey Tai Skyler Rian

Now we’re getting somewhere. This subset of names shows some swings instead of just waning peaks.

However, these calculations don’t account for the changing totals over time. They just use raw counts for the ratios. For example, there might have been more girl Ryleys one year, but maybe there were more girls born (or received Social Security numbers) that year also.

So instead of using raw counts, it’s better to look at rates so that values are comparable over time.

Most Switched Names, Relatively Look for names with nearly-even female-to-male maximums. But this time use rates instead of counts. 1. Kenyatta 2. Rene 3. Brighton 4. Devyn 5. Austyn 6. Ryley 7. Kodi 8. Casey 9. Azariah 10. Jael 2018 More girls More boys 1930 11. Lorin 12. Landry 13. Arden 14. Raleigh 15. Jackie 16. Stevie 17. Monroe 18. Skyler 19. Shea 20. Sol 21. Ashtin 22. Remy 23. Aven 24. Tristyn 25. Isa 26. Jaedyn 27. Carrol 28. Codi 29. Gentry 30. Daylin

Ryley is still in the top ten, but Kenyatta takes the top spot with a couple of switches from mostly boys to mostly girls and then back to mostly boys.

It’s still missing something though. While the ratio for Kenyatta was the closest to 1, it doesn’t seem correct to call it the most switched name when there are at the most a few hundred Kenyattas in a year.

That is to say, the name switched from a few hundred boy names to a few hundred girl names during the 1930 to 2018 timespan. On the other hand, Kerry, which was also close to 1 (but not as close) showed a swing in the thousands.

So, instead of ranking by ratio alone, I considered the maximum as well. Below, the top 100 most switched names in US history. Casey, Jackie, Kerry, Jody, and Finley lead the way in the top five.

Most Switched Names, by Rate and Count Account for more even switches as well as how big the swings were too. 1. Casey 2. Jackie 3. Kerry 4. Jody 5. Finley 6. Skyler 7. Justice 8. Rene 9. Darian 10. Frankie Max span: 7,713 6,305 4,380 3,930 3,154 2,842 1,878 1,785 1,543 1,468 2018 More girls More boys 1930 11. Oakley 12. Robbie 13. Remy 14. Milan 15. Jaylin 16. Devan 17. Armani 18. Charley 19. Stevie 20. Channing 1,428 1,370 1,300 1,231 1,214 1,095 1,089 928 890 841 21. Gerry 22. Monroe 23. Kirby 24. Azariah 25. Santana 26. Landry 27. Devyn 28. Shea 29. Austyn 30. Arden 774 761 724 720 709 703 668 628 534 446 31. Kenyatta 32. Jaedyn 33. Jael 34. Carrol 35. Ryley 36. Ricki 37. Codi 38. Shay 39. Rian 40. Aven 443 411 408 391 372 343 336 334 332 316 41. Brighton 42. Tru 43. Raleigh 44. Tai 45. Ever 46. Britt 47. Ocean 48. Gentry 49. Merritt 50. Storm 299 297 296 293 288 283 282 280 279 268 51. Rosario 52. Ashtin 53. Teegan 54. Tristyn 55. Sol 56. Isa 57. Kodi 58. Torey 59. Lorin 60. Maxie 259 258 257 251 231 228 227 226 218 215 61. Ridley 62. Shia 63. Yuri 64. Linden 65. Kaedyn 66. Daylin 67. Tylar 68. Dru 69. Indiana 70. Kalin 212 203 193 186 186 185 180 179 178 178 71. Barrie 72. True 73. Jodeci 74. Tramaine 75. Shai 76. Cree 77. Allyn 78. Arion 79. Jaydyn 80. Lexington 175 174 171 168 165 161 160 160 160 159 81. Aris 82. Jaelin 83. Kylin 84. Jaidan 85. Clarke 86. Talyn 87. Ashten 88. Claudie 89. Amen 90. Krishna 158 158 157 157 156 155 153 151 151 150 91. Lakota 92. Vernie 93. Kit 94. Tenzin 95. Arin 96. Riyan 97. Jaziah 98. Parris 99. Tobey 100. Catlin 148 147 147 147 146 144 144 140 138 136

Looking closer at Casey, I’m not entirely sure if it’s so much a switched name than it became a unisex name. Well, I guess it switched to unisex. It was mostly a boy name and while remaining a boy name, it also grew popular as a girl name. I guess I can get on board with that.

Notes

The data comes from the Social Security Administration, and it continues to be a fun time series dataset to poke at. I analyzed and visualized the data in R.

See also: