But, what is the "deaths per mile walked/biked"? Put differently, people (kids included) also walk less than in the 60s or 70s because we've made it unsafe (or

But, what is the "deaths per mile walked/biked"? Put differently, people (kids included) also walk less than in the 60s or 70s because we've made it unsafe (or at least difficult and unpleasant) to do so.