A photo of part of a Monopoly board, centering -- of course -- on the Free Parking square

Donald Shoup’s The High Cost of Free Parking has been on my to-read list since I was knee-high to a grasshopper; I think I’ve delayed reading it out of a vague concern that it’s just going to tell me what I already believe. (Is anyone else with me that a lot of books are like this these days?) But I just started reading it, and the introduction has already blown my mind a little bit by giving a sense of the scope of the damage that free parking does.

Take this, for example: Shoup makes a really good point about the usual argument for cities’ requiring developers to provide parking spaces. The usual argument is that, if developers didn’t provide it, people would consume the common resource (on-street parking). But this starts from the assumption that the correct price of parking is $0.00, so that developers are required to supply the quantity of parking that would be demanded if parking were free. So the city is constantly forcing the price of parking down to $0.00.

He contrasts this with the fight over affordable housing. It takes a lot of fighting to get even a few units of affordable housing, yet “affordable parking” — in fact free parking — is just assumed.

The book is also rich in data. Citing the 1995 NPTS, Shoup notes that drivers spend an average of 73 minutes per day in the car; a quick approximation, then, says that the average car is idle for 95% of the day (i.e., 100 * (1440 – 73)/1440 percent of the day). That’s a shockingly high number. Makes my mind wander off in a couple directions:

  1. Will driverless cars really solve this, as people hope they will? Yes, cars are idle 95% of the time, but everyone is using their car at exactly the same time of day. If the supply of driverless cars needs to be matched to peak demand, will we end up with the same number of cars?
  2. Cars might resemble books, in that we own them and mostly don’t do anything with them; they mostly sit idle. Just as it’s probably more efficient to give up our personal libraries and use the public library, perhaps there’s an efficient public solution to the problem of mostly-idle automobiles. I’ve thought similar things before about snow blowers. But the problem with snow blowers feels the same as the problem with automobiles: everyone tends to want to snow-blow his driveway, or drive to work, at exactly the same time. Many library books don’t suffer from this problem: I likely want to read The High Cost of Free Parking at a different time than you do. On the other hand, maybe we all want to read the same bestseller at the same time.

There’s probably a body of economic theory that already explains the optimal allocation of these sorts of goods. I’d be interested in finding a good intro.

So anyway, Shoup looks quite promising. I hope to report interesting findings from it in this space.