MEMORANDUM TO: Secretarial Officers

Modal Administrators

From : Peter Rogoff Acting Under Secretary for Policy

, x64540

Prepared by: Roberto Ayala

Economist , Office of Economic and Strategic Analysis ; x64825

Subject: Revised Departmental Guidance on Valuation of Travel Time in Economic Analysis

________________________________________________________________________

The value of travel time is a critical factor in evaluating the benefits of transportation infrastructure investment and rulemaking initiatives. Reduction of delay in passenger or freight transportation is a major purpose of investments, and rules to enha nce safety sometimes include provisions that slow travel. As the Department expands its use of

benefit

- cost analysis in evaluating competitive funding applications under such programs as the TIGER Grant program and the High

- Speed Intercity Passenger Rail program, it is essential to have appropriate, well

- reasoned guidance for valuing delays and time savings

.

This version of the guidance updates the value of travel time savings with median

household income information from the 2012 US Census Bureau and sal ary information from the Bureau of Labor Statistics Occupational Handbook 2012. The household income data are drawn from the Census Bureau’s American Community Survey, and are not released until the September following the year in which they are collected ; the 2012 data

are thus the most recent data available. The percentages of earnings used to determine the value of travel time savings (shown in tables 1 and 2) remain unchanged. The revised dollar values of travel time savings are shown in tables 3, 4, and 5. We have also revised our estimate of future growth in real incomes based on revised projections from the Congressional Budget Office (see page 1 4 ).

DOT published its first guidance on this subject , "Departmental Guidance for the

Valuation of Trav el Time in Economic Analysis

, " on April 9, 1997, to assist analysts in developing consistent evaluations of actions that save or cost time in travel. That memorandum recommended an array of values for different categories of travel, according

to purpose, mode and distance. For each category, the Guidance specified a percentage of hourly income that would normally be used to determine the value per hour of savings in2

travel time, a range of percentages defining upper and lower bounds about the normal value for sensitivity testing, and an average hourly income level. Special values were assigned to walking and waiting time, travel by general aviation, and truck drivers.

Revised guidance, labeled as “Revision 1

, ” was issued on February 11, 2003. A fu rther

revision , labeled “Revision 2,” was issued on September 28, 2011 and adjust ed these

values for use in 2011 , incorporate d some additional values and procedures, and redefine d

the sources of data. In particular, time savings in high

- speed rail travel were identified as equivalent to those in air travel and distinguished from intercity travel by conventional

surface modes. Although we found no need to alter the normal percentages of hourly income and the ranges of percentages that were assigned in the 1997 memorandum, more recent and appropriate sources were used to specify hourly incomes. In particular, the

income data used in that guidance were derived from public and regularly updated sources that allow the Department to update the values annually. Also, the revised guidance project ed higher values of time in future years to reflect reasonably anticipated growth in

real incomes. This revision also i ncluded a bibliography of documents available online that provide an overview of the research literatu re in the field and the recommendations developed by experts in several countries.

A link to this revised guidance will be found on the Office of Transportation Policy

website at: http://ostpxweb.dot.gov/policy/reports.htm

. Questions should be addressed to Roberto Ayala , (202) 366

- 4825 or roberto.ayala@dot.gov in the Office of Transportation Policy.

Attachment

cc: Regulations O fficers and L iaison O fficers

## The Value of Travel Time Savings: Departmental Guidance for Conducting Economic Evaluations

Revision 2 (2014 Update)

Introduction

Many actions by the Department of Transportation and other governmental agencies are designed to benefit travelers by reducing the time spent in traveling. Actions in pursuit of other goals such as improv ed safety may also have the intended or unavoidable consequence of slowing travel. The purpose of this document is to state the procedures approved for use by all administrations within DOT when evaluating reductions or increases in passenger travel time that result from such actions. The value of travel time savings (VTTS ) derived here is to be used in all DOT benefit

- cost o r cost

- effectiveness analyses.

Governments employ benefit

- cost analysis to ensure that their regulatory actions and investments in transportation infrastructure will use society’s resources most efficiently and to promote transparency in decision

- makin g. Doing so often requires assigning money values to factors that lack observable market prices. As one of the most important of these factors, trave l time has been the subject of research in many countries over several decades. Individual experts and o fficial panels have reviewed and summarized this literature repeatedly as it has grown, and this document draws on that body of research and interpretation to establish procedures for use in valuing travel time consistently throughout DOT.

These expert summaries represent only a rough consensus about relevant variables and relationships among values. Because VTTS varies widely, standard values for

government decisions must ignore or simplify many important factors . A complete

model of real travel choice s would require a large number of variables and associated coefficients, yet there are no sources for most of these variables, and the coefficients

estimated from available data vary between studies and are subject to considerable uncertainty and interpret ation

. Combining individual decisions to draw conclusions for an entire society implies subjective assumptions about the influence of incomes and other personal characteristics. Therefore, the object of this guidance must be seen as

construction of a usef ul framework for assigning values to government actions, rather than distilling precise scientific conclusions from the literature or predicting travel

behavior.

The initial Departmental guidance for the valuation of travel time in economic analysis

was p ublished on April 9, 1997, and the first tables of revised values were published on February 11, 2003. Part of the reason for the long intervals between revisions was that certain data were available only from private sources or updated infrequently. The resulting delay and lack of transparency was inconvenient, confusing, and a potential cause of economic inefficiency. Consequently, we revised our guidance in 2011 to derive VTTS from public and regularly published data that permit s the Department to2 iss ue annual updates. W e use median income levels, rather than means, as consistently as possible. We believe that this approach reflect s the valuations of typical travelers in

diverse populations more reliably and yield s conclusions that are less sensitive to
fluctuations in extreme values. We also include a method by which analyses of actions that have long

- term impacts should incorporate expected growth in VTTS.

General concepts

The demand for travel is generally derived from the demand for activities i t permits at either end of the trip, just as sporting equipment is valued only for the complementary sport it permits. In contrast, travel time must be conceived as having a negative demand

, a consumer’s willingness to pay to have less of it

. This too is derived

, not from complements, but from substitutes , i.e., the time available for activities at origin or

destination , which may vary greatly in urgency

. The value of time saved from travel will depend on the traveler, the circumstances of the trip, and the available tra nsportation options. T here can be no assurance in principle that these factors will be stable. A large

share of individual trips, however, particularly commuting to work

, have similar purposes

and are repeated on daily and weekly schedul es

. By focusing on a few choices of mode

and route ( e.g., rail transit vs. private auto, toll highway vs. parallel free thoroughfare)

r esearchers have approximated explanations of travelers’ decisions with a manageable

number of variables yet with some co nfidence that their conclusions can be applied to a reasonably large share of travel by the larger community

.

The values so derived are broadly representative and practically useful for estimating

social benefits

— the purpose for which this guidance is intended. They can not be used to predict the number of travelers who would choose a specific mode or route, however. Such predictions depend on the distribution of time values over the population, rather than the most common value, and on the number of t ravelers who are close to the margin in deciding between alternatives.

The value of reducing travel time expresses three principles. First, time saved from travel could be dedicated to production, yielding a monetary benefit to either travelers or their employers. Second, it could be spent in recreation or other enjoyable or necessary leisure

activities for which individuals are willing to pay. Third, the conditions of travel during part or all of a trip may be unpleasant and involve tension, fatigue, o r discomfort. Reducing the time spent while exposed to such conditions may be more valuable than saving time on more comfortable portions of the trip. These principles underlie the distinctions among values recommended in this guidance.3 Specific topics

Reliability

Closely associated with VTTS, reliability has long been viewed as a source of utility distinct from reduction of the expected trip time. If travelers are uncertain about travel

time , they typically include a “buffer” in their schedules, leaving early and sacrificing a known amount of time at the origin to insure against a more costly delay in arriv ing at the

destination . This insurance will be frequently unnecessary or excessive and occasionally inadequate. Alternatively, insur ing against delay may mean choosing a more reliable

route or mode with a slower expected speed or a higher monetary cost.

There are several ways to measure the travelers’ experience and define their perception of future delay risks, including standard devi ation of trip time, difference between the 90 th
percentile trip time and the median (or between other convenient points on the distribution), or the probability of lateness beyond a fixed target. Furthermore, variation of travel time over some period will differ between origin

- destination pairs, depending both on the reliability of travel on each trip segment and on the correlation of delays between segments.

Thus, a “value of reliability” is much more complex to estimate than an average VTTS,

since it requires knowledge of the joint distribution of travel times and of the rates of change of value at the margins, rather than just the means. Studies have been conducted in several countries, using different measures of reliability, and suggestive results have been produced. Although it may be possible to derive estimates for specific cases, we are not yet prepared to provide guidance for routine valuation of reliability. In contrast to differences in reliability among modes or routes, however, improvemen ts in reliability on a single route will often be linked to reductions in expected travel time, so that one possible approach is to add an allowance to VTTS to reflect the value of improved reliability.

Size of time change Another subject of discussion ha s been whether VTTS should be ignored below some

threshold increment of time saved. Some research has suggested the conclusion that discrete, small savings may have negligible benefits . See Australia Bureau of Transport Economics, Fosgerau et al.

, Mackie et al

. (2001 , 2003 ).

There is no persuasive evidence of wh ere such a threshold might be for any population or how it could be used to predict an appropriate threshold for another. A more important problem is that all changes in travel time resulting fr om government actions are composed of many small er changes , and it would be impossible to identify particular changes considered big enough to affect each individual decision. To evaluate the aggregate impact of any action

, therefore , we must assume that the value of each minute

of saved time is constant, regardless of the total time required for a trip

.4 Value of Time in Freight Transportation

Most of the VTTS literature focuses on passenger travel, rather than freight transportation. Estimates have been made of the labor costs of freight vehicle operators (e.g., truck drivers or locomotive engineers) and of the operating costs of freight vehicles that would be affected by changes in travel time. The value of time to shippers (i.e., the

owners of th e freight that is being transported) can not be estimated so easily , however

. Because freight in transit represents unproductive capital that incurs an interest cost, part of the benefit of saved time will be proportional to the time saved, the interest ra te, and the value of the freight. The principal obstacle to estimating this value is likely to be the heterogeneity and uncertainty of freight categories affected by any specific time saving. Each corridor or mode would thus require a specific estimate of the composition of freight carried. The cost of freight transportation time will also be influenced by factors independent of value, such as how quickly products become obsolete (because of fashion or technological obsolescence), whether the products spo il over time (as do agricultural commodities)

, and whether some production process is dependent upon timely delivery

. Various reasons , then, explain why products may be “perishable” in the sense that their value declines appreciably while they are in transit. The cost to shippers may also depend on business practices, such as the amount of inventory kept on hand, and the likelihood of running out of inventory because of shipment delays.

The value of time in freight transportation is thus consid erably more complex than is the case in passenger travel. Although we are not yet prepared to offer guidance on this issue, we are conducting research, and hope that additional information will permit

concrete recommendations in the future.

Determinant s of VTTS

Research into VTTS is conducted, not merely to understand the motives of travel decisions taken by the sampled in dividuals, but to estimate the influence of measurable factors on other groups, often remote in time and place. E ach estimate depend s on the demographic characteristics of the traveling population, the mode, time, location, and purpose of travel, and the menu of available alternatives

, so the select ed explanatory

variables must be important for these decisions, practically observable o r published

, and

also obtainable for new samples . Not all relevant factors can be controlled for in a single study or measured consistently for new studies or populations affected by government

actions

. Our object is therefore to express VTTS in terms of a limited number of

variables that have been use d in empirical research and are likely to be available for application in new analyses . The sources of variation will inevitably be simplified and distorted, but the result may be a realistic approximation. The variables discussed here are those that are most common in the primary research literature and have been found most useful for applied evaluations.5 Trip purpose

The principal distinction in trip purpose is that between “on

- the

- clock” business travel time, for which a market wage is paid, and personal or leisure time allocated according to the traveler’s preferences. In some cases, commuting is treated as a separa te category, intermediate between personal and business, but more frequently it is included in personal travel. Research has typically found VTTS for personal travel to be lower than the hourly earning rate . This conclusion does not imply that leisure is less intrinsically desirable than paid work

. In theory, a worker’s hourly wage is equal to his marginal value of time, but with an institutionally fixed working day, this concept can be no better than an approximation. P eople who earn a s alary may have f ew opportunit ies to convert
saved time into added income , which they would have to do to equate VTTS on and off

the clock

. Inclusion of commuting in personal travel is consistent with the hypothesis of

fixed hours for salaried work. Personal travel may a lso be undertaken to enjoy the passing scenery or the qualities of a particular mode : a sports car, cruise ship, or steam

railroad . In such a case, VTTS c ould actually be negative , the individual being willing to

pay to spend more time traveling.

In business travel, though it may seem paradoxical, the treatment of commercial drivers (whose travel time is spent working) and travelers who are unable to perform work en

route should be identical. In either case, savings in travel time are made availab le for additional productive work. When work can be performed during travel by means of a laptop computer, a mobile telephone, documents on paper, or discussion among travelers, time savings may increase productivity only slightly, if at all , implying a l ower VTTS.

Personal characteristics

Demographic variables such as age, sex, education, and employment are widely incorporated as explanatory variables in social and economic research and may well influence VTTS. While they are sometimes included in empir ical studies, they are unlikely to be practical for appraising the impact of government actions . More closely associated with VTTS are the distinctions between drivers and passengers and between parents and children. Clearly, in a public transit vehicle or a car pool, each passenger may have an independent value of time, and the value of speeding the trip can be

conceived as the sum of values for individual vehicle occupant s. In private vehicles, the case is more ambiguous. Adult or child passengers may be “along for the ride” and have no pressing business that would influence the driver’s decisions. Alternatively, the driver’s motive for speeding travel may be altruistic or joint with the passengers’ (rushing a child to the emergency room or a group to a show ). Without the possibility of distinguishing the composition or motives of ridership, it must be assumed that all travelers’ VTTS are independent and additive.6 Hourly income

In theory, h ourly income influence s VTTS through two channels. The simplest model evaluates savings in paid business travel time. While workers are assumed to be indifferent between travel and other ways to spend time for which they are compensated, employers perceive their employees’ gros s compensation (including payroll taxes and fringe benefits) as the value of the productivity sacrificed to travel. In general practice,

VTTS for business

- related travel is not estimated empirical ly but is defined by th e gross compensation

.

VTTS for pe rsonal travel lacks such a theoretical formulation, and leisure time is seen instead as an object of consumption that can be substituted for other desirable objects according to individual preferences. In general, VTTS is estimated to be l ower for

persona l than for business travel . S ee Mackie et al. ( 2001). Suggested reasons include:

• Employers’ compensation costs include taxes and benefits excluded from workers’ disposable income;

• Working hours are typically fixed by employers, preventing workers from earning more by saving personal travel time;

• Compensation is spread over several family members, including non

- earners.

While such rationales are plausible, circumstances may dictate high or low willingness to pay for faster travel by either work ing travelers or dependent s, and only empirical

research can yield quantitative estimates

. Neither specifying a model of household travel decisions nor obtaining the appropriate data for estim ation is a straightforward process. Households include varied numbers of earners and dependents for whom work, school, child care, and other demands on time and income may influence VTTS in unknown

ways. T ravel by famil ie s incurs joint costs of lost time that cannot be assigned to particular members

. Besides compensation , un earned income from investments or

annuities contributes to travel budgets

. Among all of these factors

, the compensation

level of an individual traveler may not be the most important or the most accessible

variable

. Research tends to use either a few broad household income bands stated by sampled travelers or the median household incomes of the geographic areas studied

. See,

e.g. , Asensio and Matas (2008) and Smal l et al. (2005).

To adjust past estimates for application to new populations , we require income measures

that are nationwide, comparable and stable in definition

, and regularly updated and publi shed

. The most reliable variable for projecting business VTTS is the median hourly wage for all occupations

. Since median fringe benefits are not published

, the median

wage can be scaled upward to approximate the median gross compensation by multiplying by the ratio of mean gross compensation ( including fringe benefits and payroll taxes ) to mean money wages. The best variable for projecting personal VTTS is

annual median household income

. In order to present business and personal VTTS on a7 practical and comparable basis, annual household income is scaled to a n hourly rate by dividing by 2,080 hours per year , although i t should not be inferred that travelers prorate their household incomes by the hour to make decisions

.

In using hourly income as a scaling factor to transfer VTTS estimates to new times and

loc ations it has been common to assume an income elasticity of 1.0 ( a one percent
in crease in VTTS per one percent increase in income) , implying a constant proportional relationship . Some recent studies have yielded lower elasticit i es for personal travel, although they have not been unchallenged. Such studies tend to be based on cross

sectional models , which compare travelers of different incomes at the same time and

location. Apart from the credibility of particular results, the a ssumption that parameters

derived from cross

- section studies are valid for time series is problematic. Furthermore,

use of non

- unitary income elasticities would raise a serious question. If VTTS for

business travel is defined as equal to the cost of empl oyment, it must display a unitary elasticity, growing at the same rate as growing incomes, while VTTS in personal travel, with a smaller elasticity, would display slower growth. As a result, an ever

- larger discrepancy would emerge between VTTS for busines s and personal travel, negating the hypothesis of a stable ratio between them. VTTS could then be defined only for the period of each study and extrapolated to the present or the future only by complex and arbitrary calculations. Instead, w e retain the a ssumption of fixed VTTS relationships for different trip purposes and an income elasticity of 1.0 for all

. Beyond updating VTTS estimates to the present, it is appropriate to use this elasticity with the projected rate of real income growth to obtain esti mates of future VTTS, particularly when government actions are expected to have long

- lasting impacts.

Where travelers of distinct income levels use modes that are not close substitutes, VTTS may be associated with an expected income for each mode. If t here are wide and overlapping income ranges in substitutable modes, it is preferable not to differentiate

VTTS estimates on the basis of travelers’ incomes but to use a single value for all.

Mode and distance

VTTS research is often based on the factors influencing mode choice, including the comfort, privacy, and prestige subjectively ascribed to particular modes, as well as travel time and cost. Since the conclusions of this research are used primarily to evaluate time and cost benefits, analysts must c ontrol for the other factors affecting mode choice. The question remains whether differences among modes in VTTS are systematic or are accidents of specification and the data used. For example, should VTTS differ between auto drivers and bus passengers a fter other factors are taken into account? Should income differences between the groups be assumed to affect the comparative benefits of time savings? As indicated above, where modes are relatively close substitutes in location, purpose, and trip distanc e, it is appropriate to assume that the incomes and preferences of travelers are distributed identically among and within modes, yielding a

common VTTS.8 While this uniformity is appropriate among local modes, research has found evidence of a

moderate rise in VTTS with trip distance. This tendency may be seen as a consequence of the limited amount of time available for taking a long trip. In addition, it may reflect the high value of time at destinations which justify increased costs of travel and compleme ntary food and lodging. Although some governments have derived VTTS from an estimated distance elasticity, this is an awkward parameter to use, requiring a specific distance for each application, whereas a route segment or mode affected by a government

ac tion is likely to support trips of widely varying distance. A more practical approach differentiates trips by broad categories of local and intercity travel.

Certain modes, particularly airlines and high

- speed railways, are not close substitutes for

conv entional surface modes. (High

- speed railways are associated with the Core Express Corridors defined in the FRA National Rail Plan as connecting large urban areas up to 500 miles apart with 2

- 3 hour travel time and speeds between 125 and 250 mph.) Since

t hese modes charge higher fares to travelers who place a greater value on time saving, it is reasonable to derive a distinct VTTS from the higher incomes of their passengers. Although income information on travelers in these markets is limited in detail, e stimates from the 2001 National Household Travel Survey of the household incomes of air passengers on personal and business trips permit construction of expected VTTS specific to air travel. Because high

- speed rail will often compete with air travel for s imilar consumers, the same VTTS is applied to both modes.

Comfort

Travelers will vary widely in willingness to pay to shorten the time during which they are subject to uncomfortable conditions such as walking, bicycling, and standing on platforms or in vehicles. Indeed, many other conditions

— stressful driving in heavy

t raffic, exposure to weather, crowding, uncomfortable seating, and lack of personal security

— could be included in this list, but it would be difficult to assign values to all of them or measure their severity and duration. VTTS estimates already incorporat e assumptions about such condition s . Since shortening walking distances and waiting times and increasing seating are routine options in transportation planning, we assign

values to their benefits. A distinction should be noted between actions that shorte n the time period during which such conditions are experienced (reducing waiting by more frequent train service) and those that improve conditions during the whole trip (adding cars to permit more passengers to be seated). In the former case, VTTS is fixe d at a higher level while the travel time varies; in the latter, travel time is constant, but VTTS

varies.

Research and syntheses The appended bibliography compiles references, accessible via the Internet, that

demonstrate the evolution of theoretical and empirical research into VTTS and contain even more comprehensive lists of sources. These include reviews of the research literature and recommended guidance for government agencies in the U.S. and abroad. The history of the economic theory of time valuat ion is discussed in Mackie et al. (2001) and more formally in Jara

- Díaz and Guevara (1999). The pioneering articles by Becker9 (1965) and DeSerpa (1971) place time

- allocation decisions in a context of consumption choice based on utility maximization, subje ct to constraints on income and the minimum amount of time required by each activity. With its subsequent extensions, this model permits derivation of equilibrium conditions for time allocation and has provided a widely

- used basis for estimation of the pa rameters of VTTS.

Analysts have employed various techniques for estimating travelers’ willingness to pay to save time. Where behavioral patterns such as choice of route or mode can be observed and other causal factors can be controlled for, estimates a re derived from revealed preference. More frequently, stated preference methods are employed, using questionnaires to elicit hypothetical choices among trips that vary across several dimensions. This approach allows consideration of a greater number of b ehavioral alternatives and independent variables. Although revealed preference studies observe actual consumer choices, they are subject to error in the specification and measurement of the explanatory variables. Stated preference studies, in contrast, s pecify explanatory variables precisely but may be subject to errors when respondents predict their own hypothetical behavior unrealistically. Recent research has also combined these methods, using questionnaires to elicit information on the factors influe ncing real travel choices. Most research employs discrete choice techniques such as logit analysis to estimate the parameters influencing preference for specific modes or routes. As the number of published studies has grown, some investigators have also used meta

- analysis to estimate the causes of variation among the conclusions of separate investigations.

Although VTTS was first investigated in English

- speaking countries, concerted efforts to develop national models based on systematic data collection have been undertaken in the Netherlands, Switzerland, and the Scandinavian countries, as well as the United Kingdom ( U

. K .) . VTTS has also been the object of research in Latin America and Asia. While several of these studies are cited in the bibliography , we will not analyze all of their

conclusions.

There is wide agreement that the VTTS for business travel should equal the gross hourly cost of employment, including payroll taxes and fringe benefits. Because of international

differences in tax structu res, labor markets, data resources, and analysts’ view of the social groups being studied, however, the definition of hourly income varies. In theory, it is equal to the worker’s marginal product that would be sacrificed if travel were slower.

Productivi ty may vary during work hours, allowing travel to be scheduled to minimize losses and, as noted earlier, modern technology can combine work with travel. Still,

there is no well

- accepted basis for estimating how the generalized value of business

travel tim e differs from the simple gross compensation or predicting its variation in applied evaluation. All of the cited syntheses adopt the assumption that business travel time is equal to gross compensation , except for Boiteux and Baumstark (2001) , where

VTTS o n business is estimated at 61 percent of the hourly cost of employment or 85 percent of the employee’s gross salary (relating to the French system of accounts). Whether the earnings to which estimates are applied should be averages over broad or10 narrow gr oups (defined by mode, driver/passenger, or type of employment) is often

unclear.

For personal travel, the range of recommended values is broader, reflecting the absence of a theoretically compelling hypothesis. Some studies find lower VTTS for auto

pass engers than for drivers and lower values for shopping or recreational travel than for commuting. Application of such distinctions, even if consistently supported by research, would require data on the specific characteristics and travel purposes of the po pulation affected by government actions. To suggest the values developed in other countries, the following table converts VTTS for commuting auto drivers recommended in several European studies to dollars of the same years as the estimates and projects th em to 2008 dollars by the growth in U.S. median household income. These values span a range that is significant but not so wide as to suggest major specification errors or other inconsistencies. It may be observed that the values we now recommend are ne ar the

center of this distribution.

Commuter VTTS

Country Year VTTS in $/hr. US

income growth

to
2008 Equivalent

2008
VTTS

Denmark 2004 $10.98 1.13 $12.46

France 1998 $10.26 1.29 $13.27
Norway 1995 $6.32 1.48 $9.33
Spain 2005 $17.06 1.09 $18.52

Sweden 1994 $4.34 1.56 $6.77

Switzerland 2003 $15.85 1.16 $18.41

UK 2002 $7.71 1.19 $9.15

The U

. K

. practice, as seen in Mackie et al. (2003) and in the U.K.’s Transport Analysis Guidance ( TAG ) 3.5.6 (the official guidance which Mackie’s work informs), is to distinguish modes by mean income but not by distance. VTTS for commuting is set at less than 25 percent of the average for business travel and VTTS for other purposes at 90 percent of the c ommuting rate. Gwilliam suggests that the World Bank use values of 30 percent of household income per hour for adults and 15 percent for children. Boiteux also recommends 30 percent of total employment cost per hour or 42 percent of gross wages (50 perce nt of the VTTS on business). The value grows with distance at a rate that diminishes by distance bands. Austroads (the association of Australian and New Zealand road transport and traffic authorities) recognizes a range of 30 to 60 percent of average

ear nings and suggests a standard of 40 percent. Both Concas and Kolpakov and Zhang et
al. recommend a rate of 50 percent of the national average wage for both commuting and other personal trips. Boiteux and Baumstark , Mackie et al. (2003), and Zhang et al. a ll recommend explicit use of income elasticities of personal VTTS over time: 0.7, 0.8, and 0.75, respectively.11 Concas and Kolpakov assign a value of only 35 percent of the wage for reducing seated riding time on transit vehicles but value standing at 100 percent and waiting under unpleasant conditions at up to 175 percent of the wage. Boiteux recommends increasing the VTTS in urban transit by 50 percent in crowded conditions and by 100 percent for walking or waiting. Gwilliam approves a 50

- percent increa se for both walking and waiting. Both TAG 3.5.6 and Zhang et al. prescribe a VTTS twice the normal value for walking or bicycling and 2.5 times the normal value when waiting.

In sum, there is a broad consensus on the approach adopted and the relevant va riables and categories, as well as a degree of similarity in the specific values recommended. Still, neither the findings of research nor the judgments of expert panels are sufficiently

uniform to eliminate arbitrariness.

Values for DOT applications

Al l studies have acknowledged the necessity of simplifying the many occasions and determinants of VTTS into a tractable system corresponding to the information available on the sources and targets of valuation. The structure of values that we adopted in 199 7 is broadly consistent with those employed in other countries, and it continues to be useful for evaluation of the costs and benefits of government investments or regulations. As stated in the introduction, it is not specific enough to predict travelers’ demand for particular modes or routes. In the following tables, the proportions of VTTS to income for personal vs. business, local vs. intercity, and surface vs. air travel are unchanged from our initial guidance of 1997 , except for the association of hi gh

- speed rail wit h air travel,

rather than with conventional surface modes . Similarly, the ranges of high and low proportions for conceptual testing are identical. Although valuing local personal travel at 50 percent of hourly income and intercity travel at 70 percent places our estimate among the higher ones examined, it is not beyond the range estimated in several studies and commonly viewed as reasonable.

The principal changes that we adopt ed in 2011 were the sources of income data to which these proportions are applied. We use data exclusively from Federal government sources and median income values whenever possible, considering them more representative of the incomes of typical travelers than the means . We present separate VTTS estimates for different categories of transportation vehicle operators, which can be used together with passenger VTTS to derive the benefits to vehicle occupants or combined with estimates of freight time value from other sourc es to derive the benefits of time savings in freight shipment. We also calculate hourly values as annual values divided by 2,080, rather than 2,000, for the sake of consistency with the wage figures published by the Bureau of Labor Statistics (BLS). In a ddition, we give instructions, omitted in our previous guidance, on projecting VTTS to future periods in response to real income growth.

Categories of VTTS

The ratios of VTTS to hourly incomes in Tables 1 and 2, expressed as percentages, must be multipli ed by appropriate income estimates to convert them to dollar values. These12 estimates are shown in Table 3, and the resulting VTTS estimates appear in Table 4. The appropriate ranges of VTTS for comparison of alternative estimates are shown in Table 5.

The tables present additional rows of “all purposes” values; these are weighted averages of the values prescribed for personal and business travel with weights derived from the 2001 NHTS. Although person

- miles of travel are used to weight the surface mode s,

person

- trips are more appropriate for air travel because many government actions that change air travel time will be independent of trip length.

The distributions so derived are:

• Local travel by surface modes: 95.4% personal, 4.6% business;

• Intercit y travel by surface modes: 78.6% personal, 21.4% business;

• Intercity travel by air: 59.6% personal, 40.4% business.

Business travel

For “on

- the

- clock” business travelers over all distances and by every surface mode, VTTS is assumed to be equal to a nati onwide median gross compensation , defined as the sum of the median hourly wage and an estimate of hourly benefits. The median wages are obtained from the BLS National Occupational Employment and Wage Estimates.

Median benefits are not available from this source and are approximated by deriving the ratio of average total compensation (including fringe benefits ) to average wages in the Employer Costs for Employee Compensation and applying it to median wages. This extrapolation is performed for business tra velers on all modes, using the share of benefits for all workers. This procedure generates a VTTS estimate of $ 24.1 0 (the actual value is $24.12; all dollar values are rounded off to the nearest ten cents) . For all vehicle operators the benefit share app lied is derived from the series for transportation and material moving occupations. Truck drivers’ wages are estimated for a weighted average of heavy and light truck drivers from the National Occupational Employment and Wage

Estimates.

In the case of air and high

- speed rail travel, high

- cost mode s used for fast trips over long distances, we conclude that use of a distinct wage is justified. The best source for incomes of air travelers is the BTS National Household Travel Survey of 2001 (no long

distan ce travel survey has been conducted since 2001) . This survey permits estimation of distributions of household money income by trip purpose. The ratio of 2001 median household income of business air travelers (approximately $105,000) to the U.S. Census

Bu reau 2001 median household income ($42,228) represents a factor of 2.5 to be multiplied by the gross median compensation estimate for surface business travelers. Updating median household income information from the 2012 US Census Bureau ($51,017), t he re sulting VTTS is $ 60.0 0

. Recent confidential survey data suggest that income levels for high

- speed rail travelers are similar to those for air travelers, so we apply the same VTTS to high

- speed rail travelers.13 Personal travel

For local personal travel, V TTS is estimated at 50 percent of hourly median household income. The nationwide median annual household income, $ 51,017 in 20 12 , is divided by 2,080 to yield an income of $ 24.50 per hour. The local VTTS is thus $12. 25 . We distinguish local from intercity personal travel, estimating a VTTS that rises with

distance. For the latter purpose, we have adopted a ratio of VTTS to hourly income of 70 percent. The VTTS for intercity personal surface travel is then $1 7.2 0 per hour.

For personal travel by air or high

- speed rail, the above estimate of VTTS for personal intercity surface travel is multiplied by 1.9, the ratio from the NHTS of the 2001 median household income of air travelers on personal business to the nationwi de median

household income in 2001

. Updating median household income with 2012 information

from the US Census Bureau yields a VTTS estimate of $3 2.60

.

Special issues

In application, vehicle

- hours are to be converted to person

- hours by multiplying by average passenger occupancy of vehicles. Although riders may be a family with a joint VTTS or passengers in a car pool or transit vehicle with independent values, these

ci rcumstances can seldom be distinguished. Therefore, all individuals are assumed to have independent values.

Except for specific distinctions, we consider it inappropriate to use different income

levels or sources for different categories of traveler. Neither the incomes associated with published research nor the stability of the relationship between income and VTTS are certain enough to imply that fine adjustments would yield more realistic estimates. The first distinction we recognize is that betwee n personal and business (on

- the

- clock) travel; the second is that between surface travel by conventional modes and travel by air or high

speed rail. While VTTS for business travel is correlated with an estimate of passengers’ employment compensation, for vehicle operators on several modes we have provided VTTS estimates based on median compensation data by employment category as reported by the Bureau of Labor Statistics. The scale of income levels developed here is applicable nationwide, and analysts sho uld not attempt to substitute incomes for particular modes or locations. Nevertheless, estimates derived by reliable and focused research may be superior for predicting behavioral responses in specific cases.

Personal time spent walking or waiting outsid e of vehicles, as well as time spent standing in vehicles or bicycling, should be evaluated at 100 percent of hourly income, with a range of 80 to 120 percent to reflect uncertainty. As stated above, reducing the time during which uncomfortable conditions are experienced provides a benefit equal to the product of this VTTS and the reduction in time, while the benefit of improved travel conditions (such as additional seating) is equal to the product of the difference in VTTS (50 percent of hourly income) an d the total time during which discomfort would have been experienced.14 Uncertainty in the recommended values

The ratios in Table 1 represent the best single figures for defining VTTS as a fraction of hourly income. These figures, like all parameters of travel behavior, are subject to uncertainty. Table 2 summarizes a plausible range for each trip category, not necessarily symmetric about the point estimates in Table 1. The corresponding high and low dollar

estimates are shown in Table 5. In addition to evaluations based on the most likely estimates, alternative calculations using these ranges should be presented to test the sensitivity of analyses to potential errors in estimation.

Impact of income growth on VTTS

The values presented here are suita ble for evaluation of impacts in 2014 . As stated earlier, we include an income elasticity factor to incorporate the expected growth of VTTS in response to projected growth in real incomes. With an assumed elasticity of 1.0 for both business and personal VTTS and a 1. 2 percent projected annual growth rate of

real median household income over the next 30 years , as used by the Congressional Budget Office, future values of benefits of real travel time savings should be augmented by 1. 2 percent per year before discounting to present values. 1

Updating the estimated values

The Office of the Assistant Secretary for Transportation Policy will publish annual updates of VTTS to reflect growth in hourly incomes, using the data sources cited above. No updating of the percentages developed in Tables 1 and 2 is required. We will monitor and interpret available research on travel behavior and issue new guidance as appropriate.

1 Congressional Budget Office, The 2013 Long

- Term Budget Outlook, Long

- Term Budget Projections, September 2013 Release (September 17, 2013). CBO staff have informed us by private communications that they project that the growth in the median real wage will be about 0.5 percentage points smaller than the growth in the mean real wage for the period 2014

- 2024, and about 0.3 percentage points smaller than the annual growth in the mean real wage during the period 2025

- 2045.

### Table 1 (Revision 2

- corrected )

Recommended Values of Travel Time Savings

(per person

- hour as a percentage of total earnings)

Category Surface Modes*

(except High

- Speed Rail) 

### Air and High

- Speed

Rail Travel

Local Travel

-

Personal

Business

Intercity Travel

-

Personal

Business 50%

100%

70%

100% --

--

70%

100%

Vehicle operators

- 100% on all modes

* Surface figures apply to all combinations of in

- vehicle and other time. Walk access, waiting, and transfer time should be valued at 100% of hourly income
when actions affect only those elements of tra vel time.2 

### Table 2 (Revision 2

- corrected )

Plausible Ranges for Values of Travel Time Savings

(per person

- hour as a percentage of total earnings)

Category Surface Modes*

(except High

- Speed Rail) 

### Air and High

- Speed

Rail Travel

Local Travel

-

Personal

Business

Intercity Travel

-

Personal

Business 35%

- 60%

80%

- 120%

60%

- 90%

80%

- 120% --

--

60%

- 90%

80%

- 120%

Vehicle operators

- 80%

- 120% on all modes

* Surface figures apply to all combinations of in

- vehicle and other transit time. Walk access, waiting, and transfer time should be valued at 80%

- 120 % of hourly income when actions affect only those elements of tra vel time.3 

### Table 3 (Revision 2

- correcte d )

Recommended Hourly Earnings Rates

for Determining Values of Travel Time Savings

(20 12 U.S. $ per person

- hour)

Category Surface Modes

(except High

- Speed Rail) 

### Air and High

- Speed

Rail Travel

Local Travel

-

Personal

Business

Intercity Travel

-

Personal

Business $2 4

. 50

$ 24.10

$ 24.50

$ 24.1 0 $4 6.60

$ 6 0 .00

Truck Drivers $ 25.40

Bus Drivers $ 26.40 Transit Rail Operators $ 45.20 Locomotive engineers $ 37.70 Airline Pilots and Engineers $ 82. 304 

### Table 3 (Revision 2, continued)

Sources: (1) Local and intercity personal travel by conventional surface modes: median
income for all U.S. households in 20 12 ($ 51,017 ), reported in U.S. Census Bureau, Table H

- 8. Median Household Income by State: 1984 to 20 12 , divided by 2,080 hours per year

. https://www.census.gov/hhes/www/income/data/historical/household/2012/H08_2012.xls

(2) Local and intercity business travel by convent ional surface modes: Bureau of Labor Statistics, May 2012 Occupational Employment and Wage Estimates

, median wage for all occupations

, http://www.bls.gov/oes/oes_dl.htm multiplied by the ratio of mean total compensation to mean wage from BLS Employer Costs for Employee Compensation , a verage over four quarters of

2012

, ftp://ftp.bls.gov/pub/special.requests/ocwc/ect/ececqrtn.pd f

(3) Intercity personal travel by air or high

- speed rail : median hourly household income from (1), multiplied by 1.9. Intercity business travel by air or high

- speed rail : median hourly household income from (1), multiplied by 2.5 and by the ratio of me dian national employee compensation to median household income

.

(4) Truck Drivers: weighted average of May 20 12 median hourly wages of heavy

and light

- truck drivers ($ 16.97 ) from BLS National Occupational Employment and Wage Estimates; expanded to total compensation by the ratio of total compensation to wages for transportation and material moving occupations from

the 2012 Employer Cost for Employee Compensation series

. http://stats.bls.gov/oes/current/oes_nat.htm#b53

- 0000 http://data.bls.gov/PDQ/outside.jsp?survey=cm

Other vehicle operato rs: May 20 12 median hourly wages from BLS National Occupational Employment and Wage Estimates; expanded to total compensation by the ratio of total compensation to wages for transportation and material moving occupations from the 20 12 Employer Cost for Emp loyee Compensation

series.5 

### Table 4 (Revision 2

- corrected )

Recommended Hourly Values of Travel Time Savings

(2012 U.S. $ per person

- hour)

Category Surface Modes*

(except High

- Speed Rail) 

### Air and High

- Speed

Rail Travel

Local Travel

-

Personal

Business

All Purposes **

Intercity Travel

-

Personal

Business

All Purposes ** $12. 30

$2 4.10

$12. 80

$1 7.20

$2 4.10

$18

. 70 $3 2.60

$ 60.00

$ 4 3. 70

Truck Drivers $2 5.4 0

Bus Drivers $2 6.40 Transit Rail Operators $ 45.20

Locomotive engineers $3 7.70 Airline Pilots and Engineers $ 82. 306 Table 4 (Revision 2, continued)

* Surface figures apply to all combinations of in

- vehicle and other time. Walk access, waiting, transfer, and standing time should be valued at $2 4.5 0 per hour for personal

travel when actions affect only those elements of travel time.

** Weighted averages, using distributions of travel by trip purpose on various modes. Distribution for local travel by surface modes: 95.4% personal, 4. 6 % business.

Distribution for intercity travel by conventional surface modes: 78.6% personal, 21. 4 % business. Distribution for intercity travel by air or high

- speed rail : 59. 6 % personal, 40.4% business. Surface figures derived using annual person

- mile (PMT) data from the 2001 National Household Travel Survey. http://nhts.ornl.gov/ . Air figures use person

trip data.

When projecting futur e benefits of travel time savings, values should be augmented by

1. 2 percent per year before discounting to present values.7 

### Table 5 (Revision 2

- corrected )

Plausible Ranges for Hourly Values of Travel Time Savings

(2012 U.S. $ per person

- hour)

Category Surface Modes*

(except High

- Speed Rail) 

### Air and High

- Speed

Rail Travel

Low High Low High

Local Travel

-

Personal

Business

All Purposes **

Intercity Travel

-

Personal

Business

All Purposes ** $8. 60

$ 19.30

$ 9.10

$14. 7 0

$ 19.30

$1 5. 70 $14. 70

$ 2 9.00

$ 15.40

$2 2. 1 0

$ 2 9.00

$2 3. 60 --

--

--

$2 8.00

$ 48.00

$ 36. 1 0 --

--

--

$41. 90

$ 72.00

$5 4. 10

Low High

Truck Drivers $20.30 $30.50

Bus Drivers $ 21. 10 $ 31.6 0 Transit Rail Operators $ 36. 20 $ 54.2 0 Locomotive engineers $ 30.1 0 $ 4 5. 20 Airline Pilots and Engineers $ 65.80 $ 98.708 

### Table 5 (Revision 2, continued)

* Surface figures apply to all combinations of in

- vehicle and other transit time. Walk access, waiting, and transfer time in personal travel should be valued at $19. 6 0

- $2 9.40 per hour when actions affect only those elements of tra vel time.

** Weighted averages, using distributions of travel by trip purpose on various modes. Distribution for local travel by surface modes: 95.4% personal, 4. 6 % business. Distribution for intercity travel by conventional surface modes: 78.6% personal, 21. 4 % business. Distribution for intercity travel by air or high

- speed rail : 59. 6 % personal, 40.4% business. Surface figures derived using annual person

- mile (P MT) data from the 2001 National Household Travel Survey. http://nhts.ornl.gov/ . Air figures use person

trip data.

When projecting future benefits of travel time savings, values should be augmented by

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1c062

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Issues 2

- 3, April

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Tran sportation Research Part E: Logistics and Transportation Review , Volume 37,

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3. Mark Wardman, A review of British evidence on ti me and service quality valuations, Transportation Research Part E: Logistics and Transportation Review , Volume 37,

Issues 2

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4. David A. Hensher, The sensitivity of the valuation of travel time savings to the specifica tion of unobserved effects, Transportation Research Part E: Logistics and Transportation Review , Volume 37, Issues 2

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1366

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the value o f time, Transportation Research Part E: Logistics and Transportation Review

, Volume 37, Issues 2

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6. Hugh Gunn, Spatial and temporal transferability of relationships between travel demand, trip cost and travel time, Tr ansportation Research Part E: Logistics and Transportation

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7. John Bates, John Polak, Peter Jones, Andrew Cook, The valuation of reliability for personal travel, Transportation Research Pa rt E: Logistics and Transportation Review

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