Move over, Betty, Madison is taking over.
According to a survey by genealogy website findmy past.com, the most popular baby names for American girls at the time of the 1940 U.S. Census have changed seven times more frequently than the top names for boys the same year.
This striking difference between the fortunes of popular girls' and boys' names may reflect social changes over the last 72 years, said Brian Speckart, spokesman for find mypast.com, which conducted the study to mark this year's release of the records from the 1940 Census.
"We were working on taking the 1940 Census live on our site and noticed that while many of the boys names are still common today, the girls names were quite dated," Speckart said. "Because of this, we decided to kick off some research on how names have changed."
Speckart said the study involved two researchers and was completed in less than a week and uncovered surprising results about gender roles in society.
"Women's role in society has seen a revolution since 1940," Speckart said. "Men's role has changed too, though far less."
Findmypast.com researchers analyzed the records of the U.S. Social Security Administration, which has recorded baby names, based on Social Security applications for births, since 1879.
The top 10 girls' names in 1940, they found, have fallen by an average of more than 700 places in the popularity rankings - nearly seven times as far as the top 10 boys' names the same year, which have dropped an average of barely 100 places.
None of the top 10 girls' names in 1940 even make today's top 100. Three of the top 10 names from 1940 - Betty, Carol, Shirley - have now dropped entirely from the top 1,000, compared to none of the equivalent boys' names.
Betty, Carol and Shirley are now the names of deceased grandmothers and aged aunts - the names that time forgot, Speckart said..
"Baby names are like period pieces," said Josh Taylor, genealogist for findmypast.com. "Some recall a particular era, which can make them clues when researching family history. So, you can sometimes guess roughly when someone was born simply by their first name. In such cases, names can be to genealogy what carbon-dating is to archaeology."
This is far truer, however, of girls' names than of boys', the researchers discovered.
Seven of the top 10 boys' names from 1940 still are in the top 100, while three - James, David, William - remain in the top 20, and one - William - makes the top three. William is the only top 10 name from 1940 that still is in the top 10, while last year's royal wedding of Prince William and Kate Middleton seems to have further boosted its ranking.
Only one of the 10 most popular names from 1940 - Mary - is in the top 500 today, while all of the top boys' names from 1940 are.
Today, Madison is the eighth most popular baby name for girls born in the U.S. Yet, it was originally a surname (as in James Madison, fourth president of the U.S.) and then for many years a boys' first name, until it faded from use in the 1950s.
Now, Madison is the new Betty. While Betty is the biggest faller in the girls' name leagues since 1940, Madison, along with Mia and Abigail, is the biggest riser. But while Betty was the name of a housewife and cake-baker, Madison is a "power" name - a name with its own shoulder-pads and parking space in the executive lot, Speckart added.
"American women used to have names like Betty and - like Betty Draper in the TV series, 'Mad Men' - marry men with jobs on Madison Avenue," Taylor said. "Now, women are themselves called Madison and have top jobs - on Madison Avenue and beyond."
In fact, what suddenly made Madison a popular name for girls was the 1984 movie, "Splash," in which Daryl Hannah played a mermaid who adopted the name "Madison" in human form after spotting a street sign for Madison Avenue.
The report concludes that in many cases, women are taking men's first and last names as monikers.
"Anecdotally, we noticed that trend, particularly in the last five years," Speckart said. "Names do appear to come back into style. For example, there is nothing older than Biblical names and they keep coming back."
Most of the top 10 girls' names today were rare in 1940, while at least three - Madison, Mia, Abigail - did not even rank in the top 1,000.
"In 1940, you were as likely to meet a girl named Madison as a boy named Sue," Taylor said. Seven of today's top 10 girls' names have risen more than 500 places since 1940, compared to four of the boys'.
Speckart cautions parents who are contemplating an unusual spelling of a common name that it will make their child harder to find on Facebook and will be misspelled in records and on documents.
"On the plus side," he said, "it gives them a feeling of uniqueness."
For Speckart, who has no children, his favorite names are last names and names of towns as first names.
"Parker, Boston, Covey, Logan," he said. "I don't have any children, but my recent nephew is named Madsen, which is my grandmother's maiden name. Not only do I like the name, it also, in some ways, carries on the legacy of my grandmother."
Speckart said people are fascinated by names because they are extremely personal.
"They are something we carry with us for the rest of our lives and a method of us passing on about ourselves, our family and our past onto our children," Speckart said. "My middle name is the same as my father's middle name, my sister is named after my great-grandmother and my niece is named after the town in which she was born."