• Summary
• Highway Operational Performance
  • The Concern with Operational Performance
  • New Operational Performance Measures
  • Percent of Additional Travel Time
  • Annual Hours of Delay
  • Percent of Travel Under Congested Conditions
  • Cost of Congestion
  • Safety Effects of Congestion
  • Other Operational Performance Measures
    • Length of Time of Trip and Average Trip Speed
    • DVMT per Lane-Mile
    • V/SF Ratio
  • Future Research
  • System Reliability
    • Bottlenecks
    • Deployment of ITS Systems
• Transit Operational Performance
  • Frequency and Reliability of Services
  • Seating Conditions
  • Average Operating Speeds
  • Vehicle Utilization

Exhibit 4-1 highlights the key highway and transit statistics discussed in this chapter and compares them with the values from the last Conditions and Performance Report in 1999. The first data column contains the values reported in the 1999 report, which were based on 1997 data. Revisions are shown in the second column. The third column reports 2000 values.

Comparison of Highway and Transit Operational Performance Statistics with Those in the 1999 C&P Report
 

To examine highway operational performance, this chapter looks at the Percent of Additional Travel Time, Annual Hours of Traveler Delay, and the Percent of Travel Under Congested Conditions. An increase in one, two, or all three of these measures indicates a decline in mobility in the urbanized portions of the Nation.

The Percent of Additional Travel Time is an indicator of the additional time required to make a trip during the congested peak travel period rather than at other times of the day. In 2000, a trip that would take 20 minutes during non-peak, non-congested conditions would typically require 30.2 minutes if taken during the peak period of travel or 51 percent longer. In 1997, that same trip would have required 29.0 minutes if taken during the peak travel period, 45 percent longer than under non-peak, non-congested conditions.

Annual Hours of Traveler Delay is an indicator of the total time an individual loses due to traveling under congested conditions in a single year. In 2000, the average driver experienced a loss of 31.2 hours due to congestion. This is an increase of 3.1 hours over the amount of annual delay in 1997 or an increase of more than 11 percent over the three-year period.

Percent of Travel Under Congested Conditions is defined as the percentage of traffic on the freeways and principal arterial streets in urbanized areas moving at less than free-flow speeds. This measure has increased from 31.7 percent in 1997 to 33.1 percent in 2000. Based on this measure, the average congested period or length of “Rush Hour” has increased more than 18 minutes from 1997 to 2000. For the purposes of this chapter, “Rush Hour” is defined as the combined periods of time for the A.M. and P.M. travel times when traffic is moving at less than free-flow speeds. The average “Rush Hour” in 2000 was approximately 5.3 hours; however, larger communities have the potential of experiencing average lengths of congested periods of 7 to 8 hours.

Travel density continues to increase on all functional classes as daily vehicle-miles traveled (DVMT) is growing faster than new lane miles are added. DVMT per lane-mile on Interstates in urbanized areas grew from 14,361 to 15,310 between 1997 and 2000. DVMT per lane-mile on Urbanized Other Freeways and Expressways grew from 11,217 to 12,210 over this period.

The highway information presented in this chapter are based on data from the Highway Performance Monitoring System (HPMS), work supplied by the Texas Transportation Institute (TTI), and statistics from the Federal Highway Administration Fiscal Year 2003 Performance Plan.

Transit operational performance can be evaluated by examining trends in speed and in vehicle utilization rates based on operating data collected in the National Transit Database (NTD). It can also be evaluated with passenger surveys of travel time, waiting time, and seating conditions collected from nationwide surveys.

The operational performance of transit services appears to have diminished marginally over the last few years, particularly for rail modes. Passenger-mile weighted average operating speeds for all transit services combined fell from 20.3 miles per hour in 1997 to 19.6 miles per hour in 2000. The average operating speed of rail services declined from 26.1 miles per hour in 1997 to 24.9 miles per hour in 2000. Non-rail service operating speeds have remained relatively constant—13.8 miles per hour in 1997 and 13.7 in 2000. Vehicle utilization rates have increased for rail modes—commuter rail, heavy rail and light—but declined for buses and demand response vehicles. Annual passenger miles per capacity-equivalent vehicle, in thousands, increased from 814.7 in 1997 to 914.3 in 2000 for commuter rail; from 696.3 to 783.7 for heavy rail; and from 637.6 to 687.6 for light rail.

The most recent nationwide survey of transit travel for which data are available is the 1995 National Household Travel Survey. This information was also presented in the 1999 C&P report. This survey found that, in general, transit provides more reliable and comfortable service to people with higher income levels.