Here’s a chart from Donald Shoup’s The High Cost of Free Parking, showing the difference between using parking pricing to maximize revenue (i.e. setting rates higher but having fewer cars occupy spots) and setting rates at “socially optimal occupancy”, where about 80% of parking spots are occupied at any given time.

Check it out; it’s a supply and demand curve:

Basically, many cities attempt to peg parking occupancy at around 80% by using pricing… any more and you generate a lot of extra traffic, any less and you’re not adequately using the public space to its potential.

Stay tuned for more on this important topic!