As several friends of mine can verify, Saturday night I was expressing some skepticism about the idea that seventy-gillion people were really all going to schlep down to DC to stand outside in January amidst a giant crowd. Among other things, the crowd estimate sizes seemed to have been pulled out of thin air. Now I read:

Officials are casting doubt on an early projection that 4 million to 5 million people could jam downtown Washington on Inauguration Day, saying it is more likely that the crowd will be about half that size.

D.C. authorities said the earlier estimates, provided by Mayor Adrian M. Fenty (D), were based on speculation surrounding the historic nature of the swearing-in of Barack Obama as the nation’s first African American president. After weeks of checking with charter bus companies, airlines and other sources, they’re reassessing.

Duly noted. What’s more, let me say that despite widespread rumors of people reaping windfalls by renting out their houses for Inauguration Week, I have yet to encounter real hard evidence of any such thing happening.

For some reason people’s basic knowledge of price mechanisms seems to go out the window when the subject turns to parking. A ridiculously large number of people are expected to come to town for Barack Obama’s inauguration. Since one way of getting to town is on Metro, they’re anticipating record ridership figures. And many of Metro’s station are park-and-ride facilities in the suburbs — you drive there, drop your car, and drive into town. Since they’re anticipating record ridership, they’re also anticipating record demand for parking. Naturally, they’ve decided this would be a good moment for a temporary spate of free parking.

This is insane. The marginal costs associated with mass transit are close to zero. Consequently, fares and fees should really be kept as low as possible, with as much of operating costs as possible covered by direct subsidy. The exception to this guideline, however, is when you’re genuinely up against a supply constraint. When you can’t fit any more people on to your trains and there’s no good way to expand service, you need to use pricing to keep demand in check, even in an Yglesian world where transit funding was sky-high. Similarly, since we aren’t (and shouldn’t) going to build whole new parking facilities between now and Inauguration Day, the only way to avoid ridiculous parking shortages is to charge more, not less, than usual. What’s more we of course don’t live in that ideal world where public subsidy is generous enough to use fees purely for rationing purposes. Metro needs to cover some of its operating costs through fares and parking fees. And Inauguration Day is a potential bonanza in that regard.

It’s not too late to correct this error, and hopefully WMATA will think harder about this.