Calculating the Positive Externalities of Reduced Car Ownership

Michael Anderson has written a pair of posts to calculate the effect of reduced car ownership in Portland, Oregon. According to the premise of both articles, about 38,501 additional cars would be on the road in Portland if residents owned cars at the same rate as in 2007.

The first post, published in June, calculated and visualized the amount of space the reduced car ownership gains the city. For that record, "that’s everything between NE Killingsworth, Skidmore, Rodney and 16th," or "it’s the entire Foster-Powell neighborhood west of SE 73rd Avenue," among other large swaths of the city.

Andersen's newest post focuses on "the money that isn’t being spent to move, maintain, insure and replace all those cars." For each of the 38,501 cars, Andersen calculates a savings in insurance, purchase, and taxes and fees to produce a "very low estimate of direct car ownership costs per year" totaling $2,178. "So just by not owning 38,501 cars that they would have owned in 2007, Multnomah County residents are saving $83,855,178 each year to spend on other things instead," concludes Andersen.

Andersen the imagines a wish list of big ticket items that could be paid for with the money saved on reduced car-related spending, including eliminating tuition at Portland Community College, building out the entire bike plan for the city, or nearly eliminating fares on the TriMet transit system.