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11 Exhibit 5. The OUTPUTS worksheet of the DIETT spreadsheet application. 2.2.3 The CHOKE POINTS Worksheet the top tier should be about twice the number sought as the final output. For example, if the final list is to contain the top The CHOKE POINTS worksheet contains the data imported 25 TCPs for the state, the top tier should contain about 50 can- from the DIETT Query System (see Section 2.1 and Exhibit 2). didate TCPs. Refinements to the data should be made to reflect The CHOKE POINTS worksheet contains the raw data used the realistic circumstances associated with the TCP (i.e., refine by the algorithms in the OUTPUT worksheet. This is where number of trucks, detour distance, congestion level, etc.). changes to the raw data are to be performed. Suggested activ- After the data have been refined, go to the INPUTS work- ities include the following: sheet, adjust the default values, and click on the "Calculate" button. Review all data for outliers and suspicious numbers--these may be many repeats of large numbers such as 199 or 999 for detour distance, truck traffic that is larger than 30,000 2.2.4 Changes to DIETT trucks per day, bridge span that is larger than 2000 m, etc. An experienced MS Excel analyst can unhide columns G Review data for missing information for rail traffic, barge through CB to examine the detailed algorithms used in DIETT. traffic, span length, etc. (Note: span length with a value of These algorithms reflect generalized relationships and do not "0" is a correct entry indicating that an adjacent TCP can apply equally to all circumstances, TCPs, and states. DIETT can be split to accommodate two-directional traffic.) be customized to the needs of a particular state. Changes to Correct for number and detour distance for rail. the spreadsheet should be made so as to maintain structural Correct for number of barges. functionality--the relationship between the imported data and the spreadsheet should be maintained. After the top-tier TCPs are identified, additional refinements Save all structural and functional changes to DIETT in a can be made to these candidate TCPs. The number of TCPs in different file.