Why is the Ashburnham, Massachusetts area so murdery, by episodes?

Ashburnham sits high on the central New England divide in north central Massachusetts, close enough to the New Hampshire line that the water cannot decide which way to go, draining north, south, east and west into the Merrimack and the Connecticut. The mills that once ran on that water made tubs, pails and furniture, and for one decade in the 1870s the town was the second largest chair manufacturer in the world. It is a fair distance from that now: 6,315 people, a lot of open space, and about an hour and ten minutes from Boston.

Ranked 93rd overall and third in Massachusetts, the Ashburnham area claimed two episodes and three murders, and they sit at opposite ends of the map and of the calendar. Episode 462 stays in town: a single death in June 2018, on a 29-acre property. Episode 635 crosses into southern New Hampshire to Mont Vernon, 21 miles off, where two people were killed in October 2009. Both are commuter country an hour or so from Boston, and Mont Vernon, 2,580 people with very low crime to its name, had not had a murder since an 1840 tavern brawl.