In the entire United States, seven people age 12 to 14 are shot to death in an average month. In Boston, three met that fate in just the past few weeks.

First, 14-year-old Emmanuel Saintil was shot in the chest on Cummins Highway, on the Mattapan-Roslindale line, on December 22, at around 6 pm. Then at 5:45 am, on New Year’s Day, 14-year-old Jason Fernandes was shot near the intersection of Clarkson and Hamilton Streets in Dorchester.

Finally, a little past 7 pm this Saturday, 13-year-old Luis Gerena was shot multiple times — sources say seven — near the Bromley-Heath projects in Jamaica Plain.

That’s more murders in that age group than Washington, DC, has had in the past five years, with only one 13-year-old and one 14-year-old murder victim since 2002.

Over the same period, Boston suffered through four adolescent deaths: 13-year-old Katherine Herpin and 14-year-olds Michael McQuay and Eon Hoskins in 2003, and 14-year-old Dakeem Galloway in 2004.

Kids that age simply don’t get gunned down like this, except on rare occasions: in Philadelphia, for example, only one of 406 murder victims last year was age 14; none were 13 or 12.

And yet it was only a matter of time before it happened here again. For the past 16 months, the city has averaged one shooting victim a month in that age range. Until last month, the incidents had not been fatal. That couldn’t last.

In fact, we’ve been lucky. A total of 25 youngsters were shot last year, ranging in age from seven to 15, according to data provided to the Phoenix by the Boston Police Department. Saintil was the only one who died. If those young victims had died at the same rate as older Bostonians — one in seven — we would have buried three of those juveniles instead of one.

So why are so many of our youngsters getting shot? It’s hard to say, especially since none of the three recent murders has yet been solved. In fact, arrests have been made in just one of last year’s 25 shootings with a victim younger than 16. Police made arrests for less than 25 percent of last year’s total shooting homicides, and 14 percent of last-year’s total non-fatal shootings.