>>U.S. has roughly 14.5 times more people.
So the equivalent for the US would be 14.5 * 3 = 43 on a per capita basis = 2 or 3 per year over the last 9 years.
As you note, in 2015 it's more than one per day.
There is an elephant in the room.
"... They ne'er cared for us
yet: suffer us to famish, and their store-houses
crammed with grain; make edicts for usury, to
support usurers; repeal daily any wholesome act
established against the rich, and provide more
piercing statutes daily, to chain up and restrain
the poor. If the wars eat us not up, they will; and
there's all the love they bear us."
-- Shakespeare: Coriolanus, Act 1, scene 1
