3.2.1 Analysis Details
In this section, the user can enter details about the project (Figure 5). The user must enter
information on program cost, duration and approximate number of employees or commuters
affected by the program.
The total number of employees defines the size of the commuting population under study and
is used to compute baseline vehicle trips and vehicle miles of travel (VMT). Depending on the
scope of analysis, this figure can represent the size of a single employment site, the total
regional employment population, or a specific target population. For example, if running an
area‐wide analysis, employers below a certain size might not be required to participate in trip
reduction program. Therefore, the user might want to restrict the analysis to employers of a
relevant size and occupational industry.
Employer support programs tend to differ in terms of magnitude based on industry sector and
size. If conducting a site‐based analysis, the user can only select one industry sector. This
choice is mutually exclusive (i.e., no more than one sector can be selected at the same time).
This tailors specific inputs, such as the prevailing wage rate used to compute congestion cost
changes and the calculation of employer support programs impacts.
The user can check the industry sectors that are likely to be affected by the program if running
an area‐wide analysis. One or more sectors can be checked, and if the policy affects all sectors,
then the user can select all of them (Figure 6). This action uses the geographic area default
industry composition information from TRIMMS database file and affects the calculation of
baseline mode share changes, as well as the estimation of travel time savings. Default data on
sector employment levels and wage rates are displayed in the input worksheet as detailed in
Section 5.2.4 of the user manual. Wages are used to compute the congestion benefits the
project might produce. These change according to occupation and industry sector. To
customize the wages to the analysis scope, the user needs to select the occupation type by
clicking on the occupation list. This option also affects the program support evaluation as
discussed in the next section.
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