I can't find a contour plot to reference, but I saw one once to this effect: Every few decades in the US, the roaming range for kids decreasing by a factor of

I can't find a contour plot to reference, but I saw one once to this effect: Every few decades in the US, the roaming range for kids decreasing by a factor of three or more IIRC -- over generations. My father as a kid was setting animal traps all over the county, and for him a rifle, technologically speaking, was his PC.