anchor: Within the U.S. it is surprising that the average postal density of the bottom quartile of routes (ranked by cost) is lower than the postal density for the rural routes serving the least densely settled 10 percent of the population (50 versus 89).
positive: The average postal density of the bottom quartile of routes is lower than the postal density for the rural routes
negative: The average postal density of the bottom quartile of routes is greater than the postal density for the rural routes