to represent the cross-price elasticity of transit trips with respect to auto parking price. This is done in the full extension of Equation (5) of the sketch planning application.

Indeed, this approach can be extended to evaluate all TDM programs or strategies affecting the generalized costs of transport and modal travel times. The estimated change in SOV trips can subsequently be used within a social welfare framework of analysis. For example, the number of SOV diverted trips can be evaluated in a benefit cost analysis fashion, where each reduced trip is valued for the societal benefits it contributes to, and discounted by the cost incurred to divert it to other modes.

The next step of the evaluation is to assess the net annualized benefits that these 138 reduced vehicle trips provide. Let us assume that the sum of per passenger-trip external costs associated with SOV is equal to $2.00 per round trip. Therefore, the average daily benefits brought about by the 138 reduced trips are:

(138 trips/day) X ($2.00/trip) = $276/day

Assuming an average of 235 working days per year, the annual benefits are equal to:

($276/day) X (235 days/year) = $64,782/year

Since the number of daily passenger-trips reduced is equivalent to the average annual daily trips (AADT) reduced, the annualized per passenger-trip benefit is equal to:

# ($64,782) / (138 AADT reduced) = $470 per AADT reduced

Now, we turn to compute the annualized cost of the program, by plugging the example numbers into Equation (6):

A = 50,000

( ) ( ) 1 0 6 . 0 1 0 6 . 0 1 0 6 . 0 2 2 ⎥ ⎦ ⎤ ⎢ ⎣ ⎡ − + +

= $27,272

# Which on a per AADT reduced basis is equivalent to:

($27,272)/(138)= $ 198 per AADT reduced

# Finally, the value of a trip removed is equal to the sum of benefits and costs:

# Value of trip removed (per AADT reduced) = $470 - $198 = $272

Another significant measure of the program effectiveness is given by the benefit to cost ratio, which is equivalent to:

$470 / $198 = 2.40

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