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32 Another trend is that the states with the most mature and Define criteria for selecting new measures, expansive performance reporting produced interpretive Identify additional candidate measures, and reports to accompany the published metrics. The Washing- Select a set of measures from the list of candidates for fur- ton State DOT's Grey Book includes more than 100 pages ther design and implementation. of metrics quarterly. In addition, the DOT accountability website includes links to other department reports of their Integrate Performance Measures into the Organization performance. The Missouri DOT's Tracker includes more than 100 mea- Engage internal and external stakeholders to achieve sures, and its monthly report includes more than 220 pages buy-in, of data and interpretation. The Minnesota DOT's Annual Identify the different decision contexts in which perfor- Transportation Performance Report tracks 16 basic areas of mance measures are to be used (project, corridor, and net- performance and includes 38 pages of explanatory material. work levels and for short- or long-range decisions) and Commonly used metrics address infrastructure condition, refine measures so that they are at the appropriate level of highway safety, project delivery, budgeting, personnel goals, sensitivity, and progress toward specific programs. Less common are Identify opportunities for using measures that are consis- mobility measures and freight measures. NCHRP Synthesis tent across different organizational units responsible for 311 reviewed the use of performance measures for the moni- various asset classes, modes, or work types, toring and operational management of highway segments Identify needs for additional data collection, data manage- and systems.3 An assessment of the relative strengths and ment, and analytic tools to support the selected measures, weaknesses of over 70 performance measures in use then was Design communication devices with formats appropriate performed. The survey of DOTs and metropolitan planning to the target audiences, and organizations (MPOs) yielded the list of performance mea- Document measure definitions and procedures. sures shown on Table 3.1. The Responses column shows how many responding agencies use the measure. Note that freight Establish Performance Targets performance measure use is low, as is the use of measures that capture real-time highway operations. Define the context for target setting and establish time Measures of the number of persons or vehicles served horizon(s), were most commonly reported as the most important mea- Determine which measures should have targets, sures, including volume, vehicle-miles traveled (VMT), Develop long-term goals based on consideration of techni- persons served expressed in person-miles traveled, and cal and economic factors, freight-volume served expressed in truck-miles traveled. Consider current and future funding availability, With respect to freight, the synthesis suggests that measures Analyze resource allocation scenarios and tradeoffs, could be developed to reflect the freight system and could use Consider policy and public-input implications for target data such as vehicle length, height, and weight, the number setting, and of axles, safety inspection statistics, truck crashes, commer- Establish targets and track progress. cial vehicle enforcement/inspection times and costs, railroad crossing protection, and weigh-in-motion information. States Use Only a Handful Public-Sector Logic for of Freight Measures Selecting Measures Although the research literature identified hundreds of NCHRP Report 5514 recommends a step-by-step process potential freight performance measures, in practice the specifically for developing asset management measures, but minority of states that have freight performance measures the process can be applied to most categories of measures: use only a handful. Mature performance measurement states such as Washington, Missouri, and Minnesota use between Identify Performance Measures 5 and 10 measures. It was noticeable that no two states had the same measures, and in most cases there were wide differ- Inventory existing performance measures and identify ences in the metrics. Although states reported freight perfor- how they are being used, mance metrics, most of the metrics were not used to calibrate Identify gaps to be addressed based on coverage of critical performance of specific state programs. Exceptions were for outcome areas for agency goals and objectives and support Missouri's customer satisfaction with its motor carrier office. for the asset-management best practices, Generic measures such as travel time in freight-significant

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33 Table Table3.1.Examined performance 3.1. Examined measures. performance measures. Performance Measure Typical Definition Responses Qualitative assessment of highway point, segment, or system Level of Service (LOS) 11 using A (best) to F (worst) based on measures of effectiveness Annual average daily traffic, peak-hour traffic, or peak-period Traffic Volume 11 traffic Vehicle-Miles Traveled Volume times length 10 Travel Time Distance divided by speed 8 Speed Distance divided by travel time 7 Incidents Traffic interruption caused by crash or other unscheduled event 6 Duration of Congestion Period of congestion 5 Percent of System Percent of miles congested (usually defined based on LOS E 5 Congested or F) Vehicle Occupancy Persons per vehicle 5 Percent of Travel Percent of vehicle-miles or person-miles traveled 4 Congested Delay Caused by Increase in travel time caused by an incident 3 Incidents Density Vehicles per lane, per period 3 Rail Crossing Incidents Traffic crashes that occur at highway-rail grade crossings 3 Travel time increases from congestion; this measure does not Recurring Delay 3 consider incidents Value of driver's time during a trip and any expenses incurred Travel Costs during the trip (vehicle ownership and operating expenses or 3 tolls or traffic) Weather-related Traffic interruption caused by inclement weather 3 Incidents Period required for an incident to be identified, to be verified, Response Times to and for an appropriate action to alleviate the interruption to 2 Incidents traffic to arrive at the scene Commercial Vehicle Number of violations issued by law enforcement based on 1 Safety Violations vehicle weight, size, or safety Evacuation Clearance Reaction and travel time for evacuees to leave an area at risk 1 Time Response Time to Period required for an incident to be identified, to be verified, Weather-related and for an appropriate action to alleviate the interruption to 1 Incidents traffic to arrive at the scene Security for Highway and Number of violations issued by law enforcement for acts of 1 Transit violence against travelers Toll Revenue Dollars generated from tolls 1 Travel Time Reliability Several definitions are used 1 Source: PBS&J. NCHRP Synthesis 311: Operational Effectiveness for Highway Segments and Systems. Transportation Research Board of the National Academies, Washington, D.C., 2003, Table 6, p. 22. 1