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Chapter 1 - Summary

Chapter 1 - Summary

In this edition of the Transportation Statistics Annual Report, the Bureau of Transportation Statistics (BTS) has focused on transportation indicators related to 15 specific topics (chapter 2) and on the overall state of transportation statistics (chapter 3).

Summary of Transportation Indicators (Chapter 2)

Chapter 2 contains transportation data and information on the following topics:1
1. productivity in the transportation sector,
2. traffic flows,
3. travel times,
4. vehicle weights,
5. variables influencing traveling behavior,
6. travel costs of intracity commuting and intercity trips,
7. availability of mass transit and number of passengers served,
8. frequency of vehicle and transportation facility repairs,
9. accidents,
10. collateral damage to the human and natural environment,
11. condition of the transportation system,
12. transportation-related variables that influence global competitiveness,
13. transportation and economic growth,
14. government transportation finance, and
15. transportation energy

Each of these topics is represented by a series of key indicators in chapter 2. The indicators are presented graphically; supporting data tables are in appendix B (see box 1).

1. Productivity in the Transportation Sector

Labor productivity in the for-hire transportation services and petroleum pipeline industries increased 20 percent between 1990 and 2000 compared with all business, which increased 23 percent. Among the modes, railroad and local trucking increased the most, by 65 percent each from 1990 to 2000. The labor productivity of Class I bus carriers, which fluctuated over the period, increased the least (16 percent).

The multifactor productivity of all private business sectors combined increased 8 percent between 1990 and 1999, while the multifactor productivity of the rail transportation subsector increased 30 percent.

These two indicators of economic productivitymultifactor and labor productivitydiffer. Labor productivity relates output to labor input, while multifactor productivity relates changes in output to changes in a set of inputs, such as capital, labor, energy, materials, and services. Economists generally consider multifactor productivity to be a more comprehensive indicator since it takes into account changes in several different inputs, not just labor. Rail is the only transportation sector for which multifactor productivity estimates are currently available. BTS has a project underway, in consultation with the Bureau of Labor Statistics to develop multifactor productivity indicators for all modal sectors.

2. Traffic Flows

Tracking the volume and geographic flow of traffic on Americas roads, rails, airports, and waterways helps to ensure that transportation infrastructure is properly maintained and has adequate capacity to meet the demand. The volume of passenger travel is measured by estimating the number of miles traveled per person for each mode (see box 2). This method takes into account the distance traveled by a vehicle and the number of people in the vehicle. Freight is measured in ton-miles, the movement of one ton of cargo the distance of one statute mile. Each of these volume measurements allows for comparisons across modes, although these comparisons are affected by data-collection methods and definitions.

Passenger miles of travel (pmt) in the United States totaled an estimated 4.7 trillion in 2000, or about 17,000 miles for every man, woman, and child. Over the decade, 1990 to 2000, pmt increased 24 percent. Excluding gas pipelines, all modes of freight transportation combined generated nearly 4.0 trillion domestic ton-miles in 2000, 20 percent more than in 1990.

In addition to studying freight and passenger volumes, it is also important to track changes in the geographic and modal distribution of freight and passenger travel in order to anticipate and alleviate areas of high congestion. Truck, rail, and waterborne freight flow maps help planners to pinpoint potential problem areas in the transportation system.

3. Travel Times

Most Americans experience some type of travel delay while driving their personal vehicle or traveling on a bus, train, or airplane. These delays can be costly for individuals, businesses, and the transportation industry. A multitude of factors can affect travel times.

In a 2003 study, BTS found that between 1995 and 2002, scheduled trip time (including connection time, where necessary) had increased in 63 percent of 246 rail city-pairs, in 68 percent of 261 air city-pairs, and in 46 percent of 250 intercity bus city-pairs.

For those using personal vehicles, highway travel times increased in 70 of 75 urban areas (93 percent) between 1990 and 2000. In 2000, it took 39 percent longer, on average, to make a peak period trip in urban areas compared with the time it would take if traffic were flowing freely.

Just over 82 percent of domestic air flights arrived on time in 2002, compared with 75 percent in 1996. Late flights amounted to 16 percent of flights in 2002, down from 23 percent in 1996. Over this period, late, canceled, or diverted flights peaked at 1.6 million in 2000, declining to just below 942,000 in 2002.

Seventy-seven percent of Amtrak trains arrived at their final destination on time in 2002, compared with 72 percent in 1993. Over these years, short-distance trainsthose with runs of less than 400 mileshave consistently registered better on-time performance than long-distance trainsthose of 400 miles or more.

4. Vehicle Weights

Vehicle traffic affects the longevity of infrastructure. Traffic, on a given highway segment, can be measured by average weights and numbers of vehicles. Another approach to assessing highway pavement stress is by estimating vehicle loadings on the nations highways. Aircraft landing weights can affect airport pavement, as can the weight of rail equipment on rail tracks. For maritime infrastructure, especially ports, vessel size (often expressed in deadweight tons (dwt)a measure of cargo capacity), rather than weight, can be of concern. As larger waterborne vessels are added to the worldwide merchant marine fleet, U.S. ports may have to expand to accommodate larger ships or decide to specialize in handling cargoes that are not affected by changes in vessel size.

The number of trucks in the U.S. truck fleet grew 23 percent between 1992 and 1997.2 In the Heavy category (over 26,000 pounds), the number of trucks grew 37 percent during the period, while medium trucks (between 6,001 and 19,500 pounds) increased 14 percent. Light trucks, which include sport utility vehicles (SUVs), minivans, vans, and pickup trucks, represented 86 percent of the truck fleet in 1997. The number of light trucks increased by 24 percent between 1992 and 1997, however, the strongest growth occurred among SUVs (93 percent) and minivans (61 percent).

Large combination trucks3 made up only 6 percent of traffic volume in urban areas in 2001 but accounted for 77 percent of urban Interstate highway loadings. In rural areas, they represented 17 percent of traffic and 89 percent of rural Interstate loadings in 2001. Between 1991 and 2001, large combination truck traffic volume grew from 14 percent to 17 percent on rural roads, while remaining the same on urban Interstate highways.

The average capacity of containerships calling at U.S. ports increased 9 percent to nearly 40,000 dwt between 1998 and 2001.4 Meanwhile, the average capacity of all types of vessels calling at U.S. ports grew 4 percent.

The average weight of each freight railcar remained fairly constantranging from 63 to 67 tonsbetween 1991 and 2001. However, this relatively steady average weight of a loaded railcar masks countervailing trends among selected freight commodities. Between 1991 and 2001, for instance, the average weight of a carload of coal was 110 tons in 2001, up from 99 tons in 1991. Coal represented 46 percent of rail freight tonnage in 2001.

5. Variables Influencing Traveling Behavior

Results from the 2001 National Household Travel Survey,5 sponsored by BTS and the Federal Highway Administration, show that the daily non-occupational travel of all people in the United States totaled about 4 trillion miles, an average of 14,500 miles per person per year. On a daily basis, the average person traveled 40 miles, 88 percent of it in a personal vehicle.6 Overall, people took 411 billion daily trips in 2001, an average of 1,500 trips per person annually or about 4 trips per day. The largest number of daily trips (45 percent) were to shop, to visit doctors and dentists, and for other family and personal business. Commutingtrips made to and from workaccounted for 15 percent of all personal trips in 2001. The average length of these trips was 12 miles.

One key factor affecting travel behavior is household vehicle availability. Slightly less than one-third of households had one personal vehicle available for use in 2001. A little more than one-third of households (40 million out of 107 million households) had two vehicles and slightly less than one-quarter had three or more vehicles available. Almost 8 percent of households (8.5 million) had no vehicle available for use. People in these households tend to take fewer trips and travel shorter distances each year than people in households with at least one vehicle available.

6. Travel Costs of Intracity Commuting and Intercity Trips

On average, U.S. households spent $7,406 (in chained 1996 dollars) on transportation in 2001. This represented 21 percent of all household expenditures. Only housing cost more (31 percent). On average (median), half of the working poor spent almost 10 percent of their income (based on current 1999 dollars) on commuting expenses in 1999. This is over twice the percentage of income that the median of the total population spent on commuting (4 percent).

Driving an automobile 15,000 miles per year cost 50 per mile in 2001, or 16 percent more than it did in 1991, when total costs were 43 (in chained 1996 dollars). For those using transit, the average fare remained about the same between 1990 and 2000 (in chained 1996 dollars). Increases in fares per passenger-mile for some modes of transit were offset by lower fares per passenger-mile for other modes.

On average, intercity trips via Amtrak cost 20 per revenue passenger-mile in fiscal year 2000, up 33 percent from 15 per revenue passenger-mile in fiscal year 1993 (in chained 1996 dollars). Meanwhile, average intercity Class I bus fares rose 27 percent, from $21 to $26, between 1990 and 2000 (in chained 1996 dollars).

As these data show, it is not always possible to compare the travel costs of intracity and intercity trips because not all mode travel costs can currently be measured in the same way. However, BTS statisticians, in collaboration with the Bureau of Labor Statistics, are investigating a new method of computing price indices for air travel. Preliminary data from this research are presented in chapter 2. This research might one day serve as a model for producing price indices for other modes, enabling better cross-modal comparisons.

7. Availability of Mass Transit and Number of Passengers Served

There were approximately 7,500 transit agencies in the United States in 2001. However, about 70 percent of the U.S. population is served by just 580 of these agencies. Transit use continues to be concentrated in specific markets, such as communities where households do not own cars, in certain large cities, and in lower income households. Approximately 40 percent of all daily transit trips are work related.7

There were 46.5 billion urban transit pmt in 2001 compared with 37.5 billion in 1991, an increase of 24 percent. As they have historically, buses had the largest pmt share in 2001, generating 19.6 billion pmt or 42 percent of all transit pmt.

While transit ridership was somewhat stagnant between 1991 and 1996, it grew steadily between 1996 and 2001 to 9 billion unlinked trips,8 an increase of 19 percent. Bus ridership comprised the majority of unlinked trips (5.2 billion) in 2001. However, rail transit ridership, with almost 3.5 billion trips in 2001, posted the strongest growth (39 percent). Since at least 1996, approximately 77 percent of all unlinked transit passenger trips (6.9 billion trips in 2001) have been made within the service area of only 30 such authorities. New York City transit alone accounted for 30 percent of all trips in 2001.

The nationwide fleet of ADA9 lift- or ramp-equipped transit buses increased to 87 percent (to 58,785 buses) in 2001 from 52 percent of the bus fleet in 1993. In 2001, 50 percent or 1,374 rail transit stations were ADA accessible. These stations serve passengers traveling via automated guideway transit, cable cars, commuter rail, heavy rail, inclined plane, light rail, monorail, and the Alaska Railroad.

8. Frequency of Vehicle and Transportation Facility Repairs

Data are not readily available to properly characterize the frequency of repairs for vehicles and infrastructure of all modes. Partly, this is because vehicle operations for many modes are in the private sector; and, as it affects profitability, this operational information can be confidential. For passenger cars, actual repair frequency data and resultant disruptions are dispersed among car owners. However, some private organizations do collect and analyze car repair data on a model/year basis.

In some cases where repair data are available, making the link to service interruptions can be problematic. In other cases, maintenance cost data are available (e.g., airlines and highways). But, again, the connection between costs and frequency and, thus, interruptions of service are not clear. Annual data are available on U.S. domestic vessel fleet capacity, but capacity results from market and other factors as well as repair downtime.

Most of the vehicle repair data for the trucks and buses operated by the nations nearly 600,000 motor carriers are not public information. A surrogate measure is data on highway truck inspections. Over 2.0 million roadside truck inspections were completed in 2001, up 25 percent since 1990. The percentage of inspected trucks taken out of service declined from 34 percent in 1990 to 23 percent in 2001.

Work zones on freeways cause an estimated 24 percent of the nonrecurring delays on freeways and principal arterials. The level of funding applied to highway maintenance is an indirect measure of the amount of maintenance activity and, thus, presence of work zones on highways. Funding for highway maintenance increased by 15 percent (in constant 1987 dollars)10 between 1990 and 2001. Pavement resurfacing represented just over half (51 percent) of the miles of federal-aid roads undergoing federally supported construction or maintenance in 2001, up from about 42 percent in 1997.11

Class I railroad companies maintained nearly 170,000 miles of track in 2001, down from nearly 200,000 miles of track in 1991. Throughout the 1990s, rail companies replaced an average of 743,000 tons of rail and an average of 12.2 million crossties each year. Railroads also periodically replace or rebuild locomotives and freight cars. On average, new and rebuilt locomotives made up 4 percent of Class I railroad fleets between 1990 and 2001.

Transit service12 interruptions due to mechanical failures remained relatively level from 1995 through 2000,13 averaging between 18 and 19 mechanical problems per 100,000 revenue vehicle-miles.

Natural disasters, accidents, labor disputes, terrorism, security breaches, and other unforeseeable incidents can result in major disruptions to the transportation system. Although a comprehensive account of these unpredictable interruptions has not been undertaken nor data compiled on them, numerous studies and other analyses have sought to evaluate the effects of individual events on the transportation system.

Terrorist attacks and security alerts have affected transportation services for decades. After the terrorist attacks of September 11, 2001, all commercial flights scheduled for September 12 were canceled. Many flights were canceled during the remainder of the month and the months that followed. Two years later, air passenger traffic has not fully recovered; however, other factors, such as an economic downturn, may have contributed to the decrease in traffic.

9. Accidents

Crashes involving motor vehicles and other transportation accidents in the United States result in tens of thousands of fatalities and millions of injuries each year. The number of fatalities and injuries per year represent a common means for evaluating the safety of each transportation mode. Dividing the number of fatalities by population and injuries by passenger-miles traveled can enable useful comparisons across time and modes. However, care must be taken in doing so, because definitions of fatalities and injuries vary by mode.

There were 45,130 fatalities related to transportation in 2001, almost 16 fatalities per 100,000 U.S. residents. This is a decline of 11 percent from 18 fatalities per capita in 1991, when there were 44,320 fatalities. Nearly 93 percent of all transportation fatalities in 2001 were highway-related.

An estimated 3.1 million people suffered some kind of injury involving passenger and freight transportation in 2001. Most of these injuries, about 98 percent, resulted from highway crashes. However, injury rates for most highway vehicle types declined between 1991 and 2001. One exception was the rate for light truck occupants, which rose 15 percent, from 50 per 100 million pmt in 1991 to 58 per 100 million pmt in 2001.

A BTS analysis of motor vehicle-related injury data for 200114 shows that there were sharp peaks in injuries associated with youth. For motor vehicle occupants and motorcyclists, the peak spanned ages 15 to 24 years; for pedalcyclists and pedestrians, the peak spanned ages 10 to 14 years. Young males exhibited a substantially greater peak in serious injuries than young females. In addition, the percentage of injuries classified as serious was greater for motorcyclists (20 percent of all motorcyclist injuries were serious), pedestrians (19 percent), and pedalcyclists (10 percent) than it was for motor vehicle occupants (7 percent).

Motor vehicle crashes in the United States cost an estimated $231 billion in 2000 (in current dollars), about $820 per person or 2 percent of the Gross Domestic Product (GDP). The largest components of the total cost (26 percent each) are market productivitythe cost of foregone paid labor due to death and disabilityand property damage.

While transportation accidents amounted to approximately 6 percent of the deaths of those under age 65 between 1991 and 2000, these fatalities represented 10 percent of the total years of potential life lost (YPLL)15 during this period. People who die from transportation accidents tend to be younger on average than victims of other causes of death.

10. Collateral Damage to the Human and Natural Environment

As people travel and freight is transported, damage can occur to the human and natural environment. Although most available environmental data is limited to these movements, transportations impact on the environment is not. It can also occur when transportation equipment and fuels are produced and infrastructure is built, during repair and maintenance of equipment and infrastructure, and when equipment and infrastructure are no longer usable and are discarded and dismantled. The extent of damage throughout these life cycles of transportation fuel, equipment, and infrastructure can vary by mode. In all cases, actual impacts on the human and natural environment are dependent on ambient levels or concentrations of pollutants and rates of exposure.

Transportation vehicles and vessels in 2001 emitted 66 percent of the nations pollution from carbon monoxide (CO), 47 percent of nitrogen oxides (NOx), 35 percent of volatile organic compounds (VOC), 5 percent of particulates, 6 percent of ammonia, and 4 percent of sulfur dioxide. Highway vehicles emitted almost all of transportations share of CO emissions in 2001, 80 percent of the NOx, and 75 percent of all VOC. With the exception of ammonia, transportation air emissions have declined since 1991.

Transportation emissions of greenhouse gases (GHGs) grew 22 percent between 1990 and 2001, while total U.S. emissions rose 13 percent to 6,936 teragrams of carbon dioxide (CO2) equivalent (TgCO2Eq).16 Of this, 27 percent were emitted by transportation. Nearly all (97 percent) of CO2 emissionsthe predominant GHGare generated by the combustion of fossil fuels. Transportation was responsible for 31 percent of all U.S. CO2 emissions in 2001. Transportation CO2 emissions grew 24 percent between 1991 and 2001.

Transportation-related sources typically account for most oil spills into U.S. waters reported each year to the U.S. Coast Guard. For instance, transportations share of the total volume of oil spilled between 1991 and 2000 varied from a high of 97 percent (in 1996) to a low of 77 percent (in 1992). The volume of each spill varies significantly from incident to incident. One catastrophic incident can, however, spill millions of gallons into the environment.

Transportation firms reported more than 17,700 hazardous materials incidents in 2001.17 These incidents resulted in 7 deaths and 143 injuries, compared with annual averages of 21 deaths and 445 injuries between 1991 and 2001. During that decade, the number of reported hazardous material incidents increased. However, much of the increase may be attributed to improved reporting and an expansion of reporting requirements.

11. Condition of the Transportation System

Two major components of the transportation systemvehicles and infrastructureare prone to deterioration due to wear, aging, and damage. Another component, capacity, is important to understand to aid planners in meeting the demands for travel and shipping affected by, say, congestion. Measures of the net capital stock of the transportation systemthe value in dollars of vehicles, infrastructure, and other componentsprovide comprehensive indicators that combine system condition (quality) with capacity (quantity). This measure gives a sense of the amount of money invested in the system over time and allows for comparisons across modes.

Highway-related capital stock (highway infrastructure, consumer motor vehicles, and trucking and warehousing) represented the majority of the nations transportation capital stock in 2000 (at $2,166 billion, in 1996 chained dollars). Rail also represented a substantial portion of transportation capital stock; although, it was still less than one-sixth of highway-related capital stock. The combined value of privately owned capital stock for other modes of the transportation system, including rail, water, air, pipeline, and transit, is less than the value of consumer motor vehicles alone. All highway-related capital stocks increased between 1990 and 2000. In-house transportation grew 81 percent, while transportation services (a component of all modes) rose 83 percent.

Individual data on vehicle and infrastructure condition are collected by several operating administrations of the U.S. Department of Trans-portation, such as the Federal Highway Administration and the Federal Aviation Administration. These data reflect qualitative evaluations of the pavement and associated structures.

The condition of highways, bridges, and airport runways have all improved in recent years. The percentage of rural Interstate mileage in poor or mediocre condition declined from 35 percent in 1993 to 14 percent in 2001. Moreover, poor or mediocre urban Interstate mileage decreased from 42 to 28 percent during this same period. Of the nearly 600,000 roadway bridges in 2001, 14 percent were deemed structurally deficient and 14 percent functionally obsolete. Ten years earlier, about 40 percent of bridges were either structurally deficient or functionally obsolete. At the nations commercial service airports, pavement in poor condition declined from 5 percent of runways in 1990 to 2 percent in 2001. For the larger group of several thousand National Plan of Integrated Airport Systems airports, poor conditions existed at 5 percent of runways in 2001, down from 10 percent in 1990.

The age of various transportation fleets is another measure of condition, although not a very precise one. The equipment in air, rail, highway, water, and transit transportation fleets varies widely in terms of scheduled maintenance, reliability, and expected life span. Additional information, such as fleet maintenance standards, actual hours of vehicle use, and durability, would provide a more thorough means for analyzing the condition of a vehicle fleet and comparing fleets across modes.

Because of improvements in the longevity of passenger cars, the median age of the automobile fleet in the United States has increased significantly since 1992. The median age of the truck fleet,18 by contrast, began to increase in the early 1990s but has been declining since 1997 as new purchases of light trucks have increased substantially.

The age of transit vehicles varies by transit and vehicle type. For instance, ferryboat fleets have aged, while the average age of full-size transit buses has decreased between 1990 and 2000. Similarly, the age of the U.S. maritime flag vessel fleet varies by vessel type. While 28 percent of the overall U.S. flag vessel fleet was 25 years old or more in 2000, 50 percent of towboats and 43 percent of tank and liquid barges were 25 years old or older in 2000.

The average age of Amtrak locomotives and railcars has declined by a year between 1990 and 2000. Of the 20,028 Class I freight locomotives in service in 2000, 37 percent were built in 1990 or later. While these data on rail equipment are publicly available, data on the condition of infrastructure are not released by the nations private railroads.

Finally, the average age of all U.S. commercial aircraft was 13 years in 2000, up from 11 years in 1991. While the average age of aircraft belonging to the major airlines was also 11 years in 1991, it was a year younger than the fleet average in 2000.

12. Transportation-Related Variables That Influence Global Competitiveness

Transportation contributes to economic activity and to a nations global competitiveness as a service, an industry, and an infrastructure. It affects the price competitiveness of domestic goods and services because final market prices reflect transportation costs.

The United States had relatively lower prices for transportation goods and services in 199919 than 15 out of 25 Organization for Economic Cooperation and Development countries. However, the nations top two overall merchandise trade partners, Canada and Mexico, had lower relative prices in 1999 than the United States.

The United States traded $300 billion worth (in current dollars)20 of transportation-related goods (e.g., cars, trains, boats, and airplanes and their related parts) in 2002 with its partners, more than twice the nominal value of these commodities in 1990. As is the case with overall international trade, the United States had a merchandise trade deficit in transportation-related goods exports and imports, totaling $82 billion in 2002.

U.S. trade in transportation services in 2002 totaled $105.4 billion (in current dollars). The United States had a surplus in transportation services from 1990 through 1997. Then, between 1997 and 1998, imports increased 7 percent while exports decreased 5 percent, resulting in a $4.6 billion deficit. This deficit continued to grow, reaching $13.9 billion in 2002.

Since competitiveness implies advantages in exporting certain products, these measures indicate the relative U.S. position in transportation-related goods and services. While these measures are good indicators of export performance, they only indirectly measure the relative competitive position of the United States, because several other factors besides trade influence competitiveness. A central concept that underpins trade among nations, sectors, industries, and firms is comparative advantage. Comparative advantage in trade occurs when trading partners seek to benefit from the ability to produce goods or services more efficiently or cost-effectively than other countries. The implication of this concept is that no country has a comparative advantage in the production of every good and service. In this sense, competitiveness refers to the advantage one country may have over other nations in exporting certain products, with the ultimate goal being the improvement of the countrys prosperity and standard of living.

13. Transportation and Economic Growth

Transportation comprises a sizable segment of the U.S. economy. Total transportation-related final demand rose by 37 percent between 1990 and 2001 (in 1996 chained dollars), from $719.8 billion to $984.1 billion. This measurethe value of transportation-related goods and services sold to the final usersis a component of GDP and a broad measure of the importance of transportation to the economy. In 2001, the share of transportation-related final demand in GDP was 11 percent, the same as in 1990.

The contribution of for-hire transportation industries to the U.S. economy, as measured by their value-added (or net output), increased (in 1996 chained dollars) from $181 billion in 1990 to $270 billion in 2001. In the same time period, this segments share in GDP fluctuated slightly, increasing from 2.7 percent in 1990 to 3.0 percent in 1999 before declining to 2.9 percent in 2001. This is also a component of GDP but cannot be added to transportation final demand because the two measures reflect different approaches (supply-side and demand-side) to assessing the relationship between transportation and the economy.

14. Government Transportation Finance

Governments collect revenues and spend money on transportation-related infrastructure and equipment. Federal, state, and local government transportation revenues targeted to finance transportation programs21 increased 38 percent from $82.2 billion in 1990 (in 1996 chained dollars)22 to $113.6 billion in 2000.

Spending on building, maintaining, operating, and administering the nations transportation system by all levels of government totaled $149.0 billion in 2000 (in 1996 chained dollars). Among all modes of transportation, highways receive the largest amount of total government transportation expenditures. In 2000, this amounted to $93.6 billion and accounted for nearly 63 percent of the total.

Gross government transportation investment,23 including infrastructure and vehicles, is a measure of the building of new public transportation capital. As a major component of the nations total transportation capital stocks, gross investment has risen steadily over the last decade from $59.0 billion in 1990 to $76.0 billion in 2000, an increase of 29 percent (in 1996 chained dollars).

15. Transportation Energy

Transportation energy use rose 22 percent between 1991 and 2001, to 28 percent of the nations total energy consumption in 2001. Still, transportation energy use has grown more slowly than GDP over the decade, indicating that the U.S. economy is gradually becoming less energy intensive and, thus, less vulnerable to changes in energy prices. Highway vehicles consumed an estimated 81 percent of transportation sector energy in 2001.

Transportation fuel prices experienced short-term fluctuations (in 1996 chained dollars) between 1992 and 2002. However, per capita vehicle-miles traveled (vmt) for all modes of transportation increased in almost every year. For instance, between 1991 and 2001, per capita highway vmt rose about 1 percent annually, while that of large air carriers grew 3 percent.

Passenger travel overall was 5 percent more energy efficient in 2000 than in 1990, mainly due to gains by domestic commercial aviation. (Improved aircraft fuel economy and increased passenger loads resulted in a 32 percent gain in commercial air passenger energy efficiency between 1990 and 2000.) Freight energy efficiency (ton-miles/BTU) declined 7 percent from 1990 to 2000. The decline in freight energy efficiency occurred as a result of a 2 percent average annual growth rate in ton-miles paired with a relatively rapid average annual growth rate of 3 percent in freight energy consumption.

Summary of The State of Transportation Statistics (Chapter 3)

Chapter 3 presents an overview of the state of transportation statistics. It focuses on five core areas: freight, passenger travel, air transportation, economic, and geospatial data. Each section provides an analysis of why these data are important, a review of existing data, and possible options for filling crucial data gaps.

1. Freight Data

Changes in freight transportation reflect the dynamic nature of the national and global economies and continuing improvements and innovations in technology. Alterations in the mix of manufactured products, shifts in global production and trade patterns, and growing domestic demands from industry and consumers all affect freight transportation and related data needs.

The consensus among the transportation community on collected freight data is that they are often too out of date to capture current developments and despite progress, there are many missing pieces to the freight picture. Furthermore, data are often not comparable across modes. Current data collections include the Commodity Flow Survey and the Carload Waybill Sample; data on waterborne commerce, air freight, and motor carriers; and data covering international shipments. Despite the wealth of these data, important gaps remain in data on freight flows, origins and destinations of shipments, commodities shipped, transit times, shipment costs, the nodal connections through which freight passes, and infrastructure and equipment used to sustain freight flows.

Options to improve freight data center around enhancing the Commodity Flow Survey. They include changing from the current five-year cycle to more frequent data collection and expanding coverage. Other approaches focus on standardizing the universal bill of lading and using information technologies to aid in collecting data.

2. Passenger Travel Statistics

A much-valued feature of American life is the ability to travel from place to place with relative ease, at a reasonable expense, and in a minimal amount of time, whether it isacross town, cross country, or to a foreign destination. Americans average 1,500 trips annually, covering an average of 14,500 miles per person.24

Many kinds of data are needed to evaluate (and forecast) this demand for passenger travel and how well the supply meets the demand. Data are needed for the different modes of transportation and at various levels of detail, including geographic scale. Questions that help evaluate the needs of current and future travelers include why people travel, how and when they travel, what their origins and destinations are, how long travel takes, and how much it costs. Travel data, in combination with other types of data, can also be used to assess the costs and benefits of travel, including transportation safety and its environmental effects.

There are three main types of passenger travel data: survey, regulatory/administrative, and operations/industry data. Each type provides different levels of detail in terms of coverage, periodicity, and geography; and each possesses different strengths and weaknesses. The principal surveythe National Household Travel Survey (NHTS) and its precursorshas been conducted periodically. The 2001 NHTS, conducted by BTS and the Federal Highway Administration (FHWA), asked 26,000 households nationwide about their daily non-occupational travel, as well as about long-distance trips (trips of 50 miles or more one way) taken during a 4-week period.

Other surveys that provide travel data include the long form of the decennial census (U.S. Census Bureau), Survey of International Air Travelers (Department of Commerce), General Aviation and Air Taxi Activity Survey (Federal Aviation Administration), airline passenger Origin and Destination Survey (BTS), and Vehicle Inventory and Use Survey (FHWA). Regulatory and administrative sources of passenger data include the NationalTransit Database (Federal Transit Administration) and the Highway Performance Monitoring System (FHWA). The Federal Transit Administration collects data from transit authorities; FHWA, from state departments of transportation. Industry sources that release operations data include the American Public Transportation Association (transit), Amtrak, and airline associations.

Options to improve passenger travel data include: expanding coverage of key existing datasets to additional modes, improving the specificity of intercity bus and rail data, enhancing data on rural transportation, collecting data on populations with special needs, and working on the detail and completeness of existing travel datasets.

3. Air Transportation Statistics

Airline traffic and financial statistics were first collected by the federal government in the 1930s for use in monitoring and promoting the fledgling air transport industry. Today, the U.S. Department of Transportation (DOT) collects a variety of air passenger and freight statistics from more than 240 domestic and foreign airlines serving the United States.

The federal governments use of air transport data supports policy initiatives and international air service negotiations, monitoring of air carrier fitness, allocating airport improvement funds, ensuring the provision of essential air services, setting international and intra-Alaska mail rates, and safety and security analysis. Other agencies uses of the data vary. For instance, the Department of Labor uses aviation data in their computation of productivity and consumer price indices. The Department of Justice uses data to monitor the collection of customs service fees and for anti-trust cases. Other uses range from airport planning, traffic forecasting, and development of tourism initiatives by state and local governments; travel planning by the general public; planning and marketing by the travel and tourism industry; and forecasting and analysis by airlines.

The four main categories of airline statistics that now exist, financial, operational and traffic, pricing and fees, and safety, provide different levels of detail in terms of coverage, periodicity, and focus. The federal government collects the majority of publicly available aggregated airline statistics directly from air carriers. The Air Transport Association reports member data on a quarterly and monthly basis on airfares, a cost index, and passenger and cargo traffic. The International Civil Aviation Organization collects international air data covering 188 countries.

Options to improve air transportation data include implementation of current BTS research on computing price indices for air travel, combining traffic data on air taxis and corporate jets with information from the National Transportation Safety Board for conducting exposure/risk analysis, expanding the collection of on-time statistics to smaller carriers and international flights, and allowing collection of flight-specific air transportation data.

4. Transportation Economic Data

Transportation economics refers to industry performance on key economic measures such as prices, quantities, productivity, and externalities. It looks at not only how the industry performs directly in meeting the needs of its customers, but also how it affects the economy as a whole, based on, for example, measures of employment, output, and international competitiveness.

Currently available economic data fall into several categories: prices, quantities, investment, productivity, externalities and regulation, and impacts of the economy. Price may be the measure on which customers most often focus. Good passenger travel price data exist for some modes but not for others. Some data are available for freight movement but are limited in a number of ways. Quantity data measure the level of mobility that transportation enables. Again, the availability of these data vary between passenger travel and freight and among modes.

Investment data relate to both the capacity and condition of the system. Capital stock data are available for the private transportation sectors but not for publicly owned sectors. Productivity measures how effectively economic inputs are converted into output. Two forms are used: labor and multifactor productivity. While data for the former are widely available, only railroad industry multifactor productivity data are available.

Measures of the costs of external effects of transportation (e.g., on safety, congestion, and the environment) are important in determining whether various kinds of regulation of transportation are appropriate. Data on the physical quantity of most of these externalities are available. Exact locations, costs, actual impacts, and other data are less available.

Options for improving transportation economic data include: further development of the BTS airfare price index, expansion of the Transportation Satellite Accounts data to additional modes and services, augmentation of capital stock data, and development of multifactor productivity measures for modes other than railroads.

5. Geospatial Data

Geospatial information technologies have become increasingly useful decisionmaking tools for the transportation industry and agencies responsible for transportation planning and asset management. Previously used only by expert operators on specialized mainframe systems, they are now available for desktop systems and distributed computing services that give nontechnical users access to spatial analytical tools.

BTS creates, maintains, and distributes geospatial data (on rail and highway networks, airports and runways, ports, and Amtrak stations) by state, county, congressional district, and metropolitan statistical area boundaries. The National Bridge Inventory maintained by FHWA contains information describing locations and conditions that can be displayed cartographically and analyzed. In partnership with the DOT Office of Intermodalism and FHWA, BTS developed GeoFreight,25 a tool enabling analyses of the intensity of infrastructure use for intermodal facilities (e.g., airports, seaports, and truck-rail interchanges).

Key areas for future geospatial data and standards development critical for transportation analysis include land-use planning, employee-based travel pattern analysis, and fine-grained data on infrastructure and operations critical to transportation safety and security analysis. Specific areas include: integration of bridge, tunnel, and transit data in the National Transportation Atlas Database; development of a North American Transportation Atlas Database; and expansion of a current web-based mapping center to enable customers to generate interactive maps and spatial analysis.


While a wealth of data exist to inform stakeholders about the state of transportation, much work remains to be done. Data need to be collected or collected differently, relevant linkages among datasets need to be established, and data need to be analyzed and offered in ways useful for stakeholders atall levels of government and the private sector.


1 Topics 1 through 12 appear in the Transportation Equity Act for the 21st Century, under 49 USC 111(c)(1). Some of the topic names, however, have been shortened in this report.

2 These data,from the Vehicle Inventory and Use Survey conducted every five years, were the most recent available when this report was prepared.

3 Large combination trucks weigh more than 12 tons and have 5 or more axles.

4 1998 is the first year for which data are available.

5 See box 2 on page 5 for a discussion about pmt data. Full details of the 2001 National Household Travel Survey are in chapter 2, section 5.

6 Comprises cars, vans, SUVs, pickup trucks, other trucks, recreational vehicles, and motorcycles.

7 The datum in this sentence is from the 2001 National Household Travel Survey (see section 5 in chapter 2 for more information). The balance of the data in this summary of section 7 are from the Federal Transit Administrations National Transit Database and National Transit Summaries and Trends, 2002 draft. Full citations are available in chapter 2.

8 For a discussion of linked vs. unlinked trips, see section 7 in chapter 2.

9 ADA refers to the Americans with Disabilities Act (ADA) of 1990.

10 Instead of chained 1996 dollars, constant 1987 dollars are used here because the Federal Highway Administration publishes its data accordingly.

11 1997 is the earliest year for which these data are available.

12 See detailed definitions of the type of transit equipment included in this section in chapter 2.

13 Data prior to 1995 and later than 2000 were collected using different definitions of what constitutes an interruption of service and are not comparable.

14 This analysis was based on data from the U.S. Consumer Product Safety Commission’s National Electronic Injury Surveillance System. Due to methodological differences, these data are not necessarily consistent with other injury data in this report that come from the U.S. Department of Transportation, National Highway Traffic Safety Administration’s National Automotive Sampling System General Estimates System.

15 YPLL, which is computed by adding up the remaining life expectancies of all victims at their deaths, is a measurement that accounts for the age distribution among different causes of injury mortality and other common causes of death.

16 Including sinks, net U.S. emissions totaled 6,098 TgCO2Eq in 2001. See section 10 in chapter 2 for more information on sinks.

17 See this section in chapter 2 for a definition of a reported incident.

18 This includes all truck categories: light, heavy, and heavy-heavy.

19 1999 is the most recent year for which comparable international data were available at the time this report was prepared.

20 All dollar amounts in this section are in current dollars. While it is important to compare trends in economic activity using constant or chained dollars to eliminate the effects of price inflation, it is not possible to do so in this instance (see notes on chapter 2 figures and corresponding tables in appendix B).

21 See this section in chapter 2 for detailed descriptions of the government revenues included.

22 All dollar values in the summary of this section are expressed in 1996 chained dollars.

23 See this section in chapter 2 for detailed descriptions of transportation investments.

24 These data are from the 2001 National Household Travel Survey. See chapter 2, section 5.

25 In earlier versions, this tool was called the Intermodal Bottleneck Evaluation Tool (IBET).

Updated: Saturday, May 20, 2017