And for those who've reached the age when driving is difficult or inadvisable, public transit can help them remain mobile and independent.

Charlie, great piece of work. This should be a no-brainer for NYC.

Congratulations.

You are now, also, an urban legend.

John McCormick

I enjoyed reading the report and playing with the model -- reminded me a little of playing with SimCity when I was younger.

But there is a flaw in the model which I think undermines some of its key conclusions -- especially the conclusion that enough revenue can be raised through its basket of proposals to replace the mass transit fairbox.

The problem stems from the that the cost-per-ride element in the model did not account for the increased parking costs brought on by the parking reform element of the proposal.  While the written report notes that the model indeed ignores this, the results of the omission are hardly insignificant.

There are two ways the parking reform element increases parking costs on drivers.  The first is that increaseing the per-hour rate, and the number of spaces governed by meters, takes money from motorists and gives it to the government.  This is estimated at $700m/year in the budgeting section of the model, which amounts to roughly $3 per trip, on average, for current traffic volumes -- a bit more if volumes fall on the increased cost.  If you counted this extra cost into the total price per trip (which you haven't), the elasticity of demand says that you'd have fewer trips, lower toll revenues, and less money for the subways.  That's problem one, and it is only of moderate size.

The second way in which the parking reform element affects total trip costs is significantly larger.  With the proposed high hourly cost of meters, and the proposed severe reduction in the number of non-metered spaces, motorists planning on spending more than a few hours in the city will no longer hunt for a free space, and will simply park in a private garage at $30/day or more -- still cheaper than the streets.  By being pushed into garages, even more costs will be borne by motorists, on the whole.  This will drive down demand, but those payments will not go to the government for use on mass transit; the money will go to private parking operators instead.

One way to estimate the impact of this second mechanism is to go to the "price to drive" and "future costs" section of the model and specify that the proportion of drivers who pay market rate for parking (either at the newly-expensive meters or in private garages) will go from the current level of 40% to a post-reform level of, say, 80%.  This adds a total of about $9 to the cost of each trip.  Based on my previous points, we can say that $3 goes to public meters, while $6 goes to private operators.  That increase in price will cut traffic significantly already, and most of that money won't even go to the government.  And we cannot go back and say that the government will actually collect much more than $700m/year, because that figure is based on the number of curbside spots that exist, multiplied by the hourly rate and a relatively high occupancy factor (75%).

After seeing a $9 increase in cost per trip (of which only $3 goes to the government), you are only left with $7 more dollars to toll until you reach the $16 level.  And that doesn't provide the revenue one needs to make transit free.

Basically, you really need to model the parking reform proposal with a lot more detail and seriousness before the rest of the model can be seen to really hold up.  One complexity I see with trying to model parking costs per trip is the possibility of "type shifting."  With increased parking costs, fewer people will drive to Manhattan and park for the day.  But more people than at present might drive for a quick visit and leave without paying for too much parking.  So it may be that the parking reform proposal will not push up per-trip parking costs by quite as much as $9, though at $8/hour for virtually all curbside parking, I don't see it being much lower, unless many trips to Manhattan just become through-trips.  But we need a more fine-grained approach to analyzing trip purpose and duration to really find out.

Or you could abandon the parking proposal, but that would have other effects on the assumptions used in the model -- notably on the last $700m in revenue which puts the free transit idea in the black by about $450m, instead of in the hole by $350m.

The model is a fun toy, but I won't be voting for a $16 congestion charge, radical parking reform, and free subways (as a package) when I move to New York just on its say-so.