In what must be an eternal mortification for teenagers, moms have been joining Facebook in droves.

Ignoring teens, the social networking giant is today quantifying Facebook momdom in the U.S., using anonymous aggregated data on users countrywide. This is part of a series of data-based observations about its membership that the company has undertaken on occasion, including one that showed how families interact on Facebook.

Turns out that highest number of Facebook moms are in the 40-49 and 50-59 age groups, with 30-39 running third. This relatively older demo — its average age is 47 — is because the analysis defined many of the moms by their connections to their children, who have to be at least 13 to get an account.

But if you instead define moms only by those who declared having a baby since last Mother’s Day, the average age drops to 30.

This is the kind of thing companies can do when they have lots of data. At our DataBeat conference in San Francisco on May 19 and May 20, we’ll be talking about all of the benefits of analyzing data.

Carlos Diuk of the Facebook’s data-science team led the data research effort. Echoing grown children who relish the days when they could scribble a heart on a piece of cardboard and fulfill the day’s gift-giving obligation, Diuk asked on his profile page:

“Mother’s Day is celebrated this Sunday in the U.S., so we did some data science. Does this count as a gift to mom, or should I still go get something?”

Given that there’s no credible way to wrap data with a big red bow, it is our responsibility to point out to Diuk that, yes, you still have to get something.

His research employed the Facebook definition of a mom: any U.S. female user who said she has children. That’s 27 million users.

When mapped to the States, the five with the highest percentage of Facebook moms — compared to the national average — are Wyoming, West Virginia, Iowa, South Dakota, and Idaho. Those with the fewest: New York, California, Virginia, Hawaii, and New Jersey.

One wonders: Are the rural states higher here because moms in those locations turn to Facebook more often to communicate?

The site also pointed to the most shared links last Mother’s Day, with No. 1 being the endlessly cute Open Letter to Moms from Kid President. And there’s a revealing graph — depressing or liberating, depending on your feelings about your mom — showing that the distance increases between a child’s and a mom’s current towns on Facebook as the child gets older.

Older average age, more moms in emptier states, farther away from children as children grow older.

Dude, better get something really nice for your mom.