Federal funding for highways is provided to the states mostly through a series of grant programs collectively known as the Federal-Aid Highway Program. Periodically, Congress enacts multiyear legislation that authorizes the nation's surface transportation programs. In 2005, Congress enacted SAFETEA-LU, which authorized $197.5 billion for the Federal-Aid Highway Program from fiscal years 2005 through 2009. In a joint federal- state partnership the FHWA, within the Department of Transportation (DOT), administers the Federal-Aid Highway Program and distributes most funds to the states through annual apportionments established by statutory formulas. Once FHWA apportions these funds, the funds are available for states to obligate for construction, reconstruction, and improvement of highways and bridges on eligible federal-aid highway routes, as well as for other purposes authorized in law. The amount of federal funding made available for highways was substantial--from $34.4 to $43.0 billion per year for fiscal years 2005 through 2009. The Highway Trust Fund was instituted by Congress in 1956 to construct the Interstate Highway System, which is currently 47,000 miles in length. The Highway Trust Fund holds certain excise taxes collected on motor fuels and truck-related taxes, including taxes on gasoline, diesel fuel, gasohol, and other fuels; truck tires and truck sales; and heavy vehicle use. In 1983, the fund was divided into the Highway Account and the Mass Transit Account. More than 80 percent of the total fund is the Highway Account, including a majority of the fuel taxes as well as all truck-related taxes (see fig. 1). Most Highway Account funds (about 83 percent) were apportioned to states across 13 formula programs during the 4 years of the SAFETEA-LU period for which data are available. Included among these 13 programs are 6 "core" highway programs (see table 1). In addition to formula programs, for the time during the SAFETEA-LU period for which final data are available: Congress directly allocated about 8 percent of Highway Account funds to state departments of transportation through congressionally directed High Priority Projects. The remaining funds, about 9 percent of the total, represent dozens of other authorized programs allocated to state DOTs, congressionally directed projects other than High Priority Projects, administrative expenses and funding provided to states by other DOT agencies such as the National Highway Traffic Safety Administration and Federal Motor Carrier Safety Administration (see fig. 2). Some of the apportioned programs use states' contributions to the Highway Account of the Highway Trust Fund as a factor in determining program funding levels for each state. Because the Department of Treasury (Treasury) collects fuel taxes from a small number of corporations located in a relatively small number of places--not from states--FHWA has to estimate the fuel tax contributions made to the fund by users in each state. Likewise, FHWA must estimate the state of origin of various truck taxes. FHWA calculates motor fuel-related contributions based on estimates of the gallons of fuel used on highways in each state. To do so, FHWA relies on data gathered from state revenue agencies and summary tax data available from Treasury as part of the estimation process (see app. II). Because the collection and estimation process takes place over several years (see fig. 3), the data used to calculate the formula are 2 years old. For example, the data used to apportion funding to states in fiscal year 2009 were based on estimated collections attributable to each state in fiscal year 2007. By the early 1980s, construction of the Interstate Highway System was nearing completion, and a larger portion of the funds from the Highway Trust Fund were being authorized for non-Interstate programs. The Surface Transportation Assistance Act of 1982 provided, for the first time, that each state would for certain programs receive a "minimum allocation" of 85 percent of its share of estimated tax payments to the Highway Account of the Highway Trust Fund. This approach was largely retained when Congress reauthorized the program in 1987. The Intermodal Surface and Transportation Efficiency Act of 1991 (ISTEA) raised the minimum allocation to 90 percent. The Transportation Equity Act for the 21st Century (TEA-21) of 1997 guaranteed each state a specific share of the total program (defined as all apportioned programs plus High Priority Projects), a minimum 90.5 percent share of contributions. It also introduced rate-of-return considerations into funds states received for the Interstate Maintenance, National Highway System, and Surface Transportation Programs. In 2005, Congress implemented through SAFETEA-LU the Equity Bonus Program that was designed to bring all states up to a guaranteed rate of return of 92 percent by fiscal year 2008. For the time period for which final data are available, fiscal years 2005 through 2008, our analysis shows that every state but one received more funding for highway programs than users contributed to the Highway Account (see fig. 4). The only exception, Texas, received about $1.00 (99.7 cents) for each dollar contributed. Among other states, this ranged from a low of $1.02 for both Arizona and Indiana to a high of $5.63 for the District of Columbia. In addition, all states, including Texas, received more in funding than their highway users contributed during both fiscal years 2007 and 2008. In effect, almost every state was a donee state during the first 4 years of SAFETEA-LU. This occurred because overall, more funding was authorized and apportioned than was collected from highway users. The account was supplemented by general funds from the Treasury. Our rate-of-return analysis has two notable features: It compares funding states received from the Highway Trust Fund Highway Account with the dollars estimated to be have been collected in each state and contributed by each state's highway users into the Highway Account in that same year. For example, for fiscal year 2008, it compares the highway funds states received in fiscal year 2008 with the amount collected and contributed in that fiscal year--data that did not become available until December 2009. Because of the 2-year lag (see fig. 3), fiscal year 2008 is the latest year for which these data are available. Thus, the final year of the original SAFETEA-LU authorization period, fiscal year 2009, is not included. Unlike other calculations used to apportion certain funds discussed further in this report, this analysis includes all funding provided to the states from the Highway Account, including (1) funds apportioned by formula, (2) High Priority Projects, and (3) other authorized programs, including safety program funding provided to states by other DOT agencies such as the National Highway Traffic Safety Administration and Federal Motor Carrier Safety Administration (see fig. 2 for a breakdown of these funds). Using the above methodology, our analysis shows that states generally received more than their highway users contributed. However, other calculations, as described below, provide different results. Because there are different methods of calculating a rate of return, and the method used affects the results, confusion can result over whether a state is a donor or donee. A state can appear to be donor using one type of calculation and a donee using a different type. A second way to calculate rate of return is to apply the same dollar return calculation method, but use contribution data that are available at the time funds are apportioned to the states. This calculation method indicates that all states were donees. The data used to calculate the rate of return per dollar contributed differs from our preceding analysis in two ways: As shown in figure 3, it uses 2-year-old data on contributions for apportionments, due to the time lag between when the Treasury collects fuel and truck excise taxes and funds are apportioned. It uses a subset of Federal-Aid Highway programs including both programs apportioned to states by formula and High Priority Projects. However, it does not include other allocated highway programs or other funding states receive from programs other DOT agencies such as the National Highway Traffic Safety Administration and Federal Motor Carrier Safety Administration (see fig. 2). Using this approach every state received more in funding from the Highway Account of the Highway Trust Fund than its users contributed for the SAFETEA-LU period. The rate of return ranged from a low of $1.04 per dollar for 16 states, including Texas, to a high of $5.26 per dollar for the District of Columbia, as shown in figure 5. This calculation results in states generally having a lower dollar rate of return than our calculation using same-year data (see fig. 4). A third calculation, based on a state's "relative share"--the amount a state receives relative to other states instead of an absolute, dollar rate of return--results in both donor and donee states. Congress defined this method in SAFETEA-LU as the one FHWA uses for the calculating rates of return for the purpose of apportioning highway funding to the states. In order to calculate this rate of return, FHWA must determine what proportion of the total national contributions came from highway users in each state. The state's share of contributions into the Highway Account of the Highway Trust Fund is then used to calculate a relative rate of return--how the proportion of each state's contribution compares to the proportion of funds the state received. A comparison of the relative rate of return on states' contributions showed 28 donor states, receiving less than 100 percent relative rate of return, and 23 states as donees receiving a more than a 100 percent relative rate of return (see fig. 6). States' relative rates of return ranged from a low of 91.3 percent for 12 states to a high of 461 percent for the District of Columbia. Like the return per dollar analysis in figure 5, this calculation includes only formula funds and High Priority Projects allocated to states, and excludes other DOT authorized programs allocated to states (see fig. 2). The difference between a state's absolute and relative rate of return can create confusion because the share calculation is sometimes mistakenly referred to as "cents on the dollar." Using the relative share method of calculation will result in some states being "winners" and other states being "losers." If one state receives a higher proportion of highway funds than its highway users contributed, another state must receive a lower proportion than it contributed. The only way to avoid this is for every state to get back exactly the same proportion that it contributed, which is impractical because estimated state contribution shares are not known until 2 years after the apportionments and allocations. Furthermore, because more funding has recently been apportioned and allocated from the Highway Account than is being contributed by highway users, a state can receive more than it contributes to the Highway Trust Fund Highway Account, making it a donee under its rate of return per dollar, but a donor under its relative share rate of return. California provides a useful example of this. From fiscal year 2005 through 2008, using same year contributions and funding across all Highway Trust Fund Highway Account allocations and apportionments, California received $1.16 for each dollar contributed. This analysis shows California as a donee state (see table 2). Alternatively, when calculating a dollar rate of return over the full SAFETEA-LU period (fiscal years 2005 through 2009) using state contribution estimates available at the time of apportionment (fiscal year 2003 through 2007 (as shown in fig. 3) and including only programs covered in rate-of-return adjustments, California remains a donee state, but received $1.04 for each dollar contributed. In contrast, using the relative share approach for the fiscal year 2005 through 2009 period, California received 91 percent of the share its highway users contributed in federal highway-related taxes, which would make it a donor state. A fourth method for calculating a state's rate of return is possible, but not normally calculated by FHWA. It involves evaluating the relative share as described above, but using the same year comparison data. Again, because of the time lag required to estimate state highway user contributions to the Highway Account, such analysis is possible only 2 years after FHWA calculates apportionments for states. Our analysis using this approach results in yet another set of rate of return answers. For example, using available data from fiscal years 2005 to 2008, the relative rate of return for California becomes 97 percent, rather than 91 percent. When this analysis is applied to all states, a state may change its donor/donee status. For example, Minnesota, Nebraska, and Oklahoma appear both as donor and donee states, depending on the calculation method. This comparison of the relative rate of return on states' contributions showed 27 states receiving less than 100 percent relative rate of return, and 24 states as receiving a more than a 100 percent relative rate of return. Table 3 shows the results for all four methods described and the wide variation of states' rate of return based on the method used. Since 1982, Congress has attempted to address states' concerns regarding the rate of return on highway users' contribution to the Highway Trust Fund. In 2005, Congress enacted in SAFETEA-LU the Equity Bonus Program, designed to bring all states up to a "guaranteed" rate of return. The Equity Bonus is calculated from a subset of Federal-Aid Highway programs, which include 12 formula programs, plus High Priority Projects designated by Congress. In brief, since SAFETEA-LU, the Equity Bonus allocates sufficient funds to ensure that each state receives a minimum return of 90.5 percent for fiscal years 2005-2006, 91.5 percent for fiscal year 2007, and 92 percent for fiscal years 2008-2009 for the included programs. The Equity Bonus provides more funds to states than any other individual Federal-Aid Highway formula program. Over SAFETEA-LU's initial 5-year authorization period, the Equity Bonus provided $44 billion to the states, while the second largest formula program, the Surface Transportation Program, provided $32.5 billion. Each year about $2.6 billion stay as Equity Bonus program funds and may be used for any purpose eligible under the Surface Transportation Program. Any additional Equity Bonus funds are added to the apportionments of the six "core" federal-aid highway formula programs: the Interstate Maintenance, National Highway System, Surface Transportation, Congestion Mitigation and Air Quality, Highway Bridge and the Highway Safety Improvement programs. States are frequently able to transfer a portion of their funds among the core programs, making funding of core programs less critical than it might be. States may qualify for Equity Bonus funding by meeting any of three criteria (see fig. 7). A state that meets more than one criterion receives funding under whichever provision provides it the greatest amount of funding. FHWA conducts Equity Bonus calculations annually. For the first criterion, the guaranteed relative rate of return, for fiscal year 2005 all states were guaranteed at least 90.5 percent of their share of estimated contributions. The guaranteed rate increased over time, rising to 92 percent in fiscal year 2009. The second criterion, the guaranteed increase over average annual Transportation Equity Act for the 21st Century (TEA-21) funding, also varied by year, rising from 117 percent in fiscal year 2005 to 121 percent for fiscal year 2009. The number of states qualifying under the first two provisions can vary from year to year. For the third criterion, a guarantee to "hold harmless" states that had certain qualifying characteristics at the time SAFETEA-LU was enacted, 27 states had at least one of these characteristics. A number of these states had more than one of these characteristics. Forty-seven states received Equity Bonus funding every year during the SAFETEA-LU period. However, the District of Columbia, Rhode Island, and Vermont each had at least 1 year where they did not receive Equity Bonus funding because they did not need it to reach the funding level specified under the three provisions. Maine was the only state that did not receive an Equity Bonus in any year. Half of all states received a significant increase in their overall Federal-Aid Highway Program-at least 25 percent over their core funding. Each state's percent increase in its overall funding total for apportioned programs and High Priority Projects for fiscal years 2005 through 2009 due to Equity Bonus funding is shown in figure 8. Additional factors affect the relationship between contributions to the Highway Trust Fund and the funding states receive. These include (1) the infusion of significant amounts of general revenues into the Highway Trust Fund, (2) the challenge of factoring performance and accountability for results into transportation investment decisions, and (3) the long-term sustainability of existing mechanisms and the challenges associated with developing new approaches to funding the nation's transportation system. First, the infusion of significant amounts of general revenues into the Highway Trust Fund Highway Account breaks the link between highway taxes and highway funding. The rate-of-return approach was designed to ensure that, consistent with the user pay system, wherein the costs of building and maintaining the system are borne by those who benefit, users receive a fair return on their investment to the extent possible. However, in fiscal year 2008 the Highway Trust Fund held insufficient amounts to sustain the authorized level of funding and, partly as a result, we placed it on our list of high-risk programs. To cover the shortfall, from fiscal years 2008 through 2010 Congress transferred a total of $34.5 billion in additional general revenues into the Highway Trust Fund, including $29.7 billion into the Highway Account. This means that, to a large extent, funding has shifted away from the contributions of highway users, breaking the link between highway taxes paid and benefits received by users. Furthermore, the infusion of a significant amount of general fund revenues complicates rate-of-return analysis because the current method of calculating contributions does not account for states' general revenue contributions. For many states, the share of Highway Trust Fund contributions and general revenue contributions are different, therefore state-based contributions to all the funding in the Trust Fund are no longer clear. In addition, since March 2009, the American Recovery and Reinvestment Act of 2009 apportioned an additional $26.7 billion to the states for highways--a significant augmentation of federal highway spending that was funded with general revenues. Second, using rate of return as a major factor in determining federal highway funding levels is at odds with reexamining and restructuring federal surface transportation programs so that performance and accountability for results is factored into transportation investment decisions. As we have reported, for many surface transportation programs, goals are numerous and conflicting, and the federal role in achieving the goals is not clear. Many of these programs have no relationship to the performance of either the transportation system or of the grantees receiving federal funds and do not use the best tools and approaches to ensure effective investment decisions. Our previous work has outlined the need to create well defined goals based on identified areas of federal interest and a clearly defined federal role in relation to other levels of government. We have suggested that where the federal interest is less evident, state and local governments could assume more responsibility, and some functions could potentially be assumed by the states or other levels of government. Furthermore, incorporating performance and accountability for results into transportation funding decisions is critical to improving results. However the current approach presents challenges. The Federal-Aid Highway program, in particular, distributes funding through a complicated process in which the underlying data and factors are ultimately not meaningful because they are overridden by other provisions designed to yield a largely predetermined outcome--that of returning revenues to their state of origin. Moreover, once the funds are apportioned, states have considerable flexibility to reallocate them among highway and transit programs. As we have reported, this flexibility, coupled with a rate-of-return orientation, essentially means that the Federal-Aid Highway program functions, to some extent, as a cash transfer, general purpose grant program. This approach poses considerable challenges to introducing performance orientation and accountability for results into highway investment decisions. For three highway programs that were designed to meet national and regional transportation priorities, we have recommended that Congress consider a competitive, criteria-based process for distributing federal funds. Finally, using rate of return as a major factor in determining federal highway funding levels poses problems because funding the nation's transportation system through taxes on motor vehicle fuels is likely to be unsustainable in the longer term. Receipts for the Highway Trust Fund derived from motor fuel taxes have declined in purchasing power, in part because the federal gasoline tax rate has not increased since 1993. In fiscal year 2008 (the last year for which data are available) total contributions to the Highway Account of the Highway Trust Fund decreased by more than $3.5 billion from fiscal year 2007, the first year of decrease during the SAFETEA-LU period. Over the long term, vehicles will become more fuel efficient and increasingly run on alternative fuels--for example, higher fuel economy standards were enacted in 2010. As such, fuel taxes may not be a sustainable source of transportation funding. Furthermore, transportation experts have noted that transportation policy needs to recognize emerging national and global challenges, such as reducing the nation's dependence on imported fuel and minimizing the effect of transportation systems on the global climate. A fund that relies on increasing the use of motor fuels to remain solvent might not be compatible with the strategies that may be required to address these challenges. In the near future, policy discussions will need to consider what the most adequate and appropriate transportation financing systems will be and whether or not the current system continues to make sense. The National Surface Transportation Infrastructure Financing Commission--created by SAFETEA-LU to, among other things, explore alternative funding mechanisms for surface transportation--identified and evaluated numerous revenue sources for surface transportation programs in its February 2009 report including alternative approaches to the fuel tax, mileage-based user fees, and freight-related charges. The report also discussed using general revenues to finance transportation investment but concluded that it was a weak option in terms of economic efficiency and other factors, and recommended that new sources of revenue to support transportation be explored. These new sources of revenue may or may not lend themselves to using a rate of return approach. We provided a draft of this to DOT for review and comment. DOT provided technical comments, which we incorporated as appropriate. As agreed with your offices, unless you publicly announce the contents of this report earlier, we plan no further distribution until 30 days from the report date. The report also will be available at no charge on the GAO Web site at http://www.gao.gov. If you or your staff have any questions about this report, please contact me at (202) 512-2834 or herrp@gao.gov. Contact points for our Office of Congressional Relations and Public Affairs may be found on the last page of this report. GAO Staff who made major contributions to this report are listed in appendix II. To determine the amount of revenue states contributed to the Highway Trust Fund Highway Account compared with the funding they received during the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU) period, we completed four analyses using Federal Highway Administration (FHWA) data. We met with FHWA and other DOT officials to discuss availability of data and appropriate methodologies. We used FHWA estimates of payments made into the Highway Account of the Highway Trust Fund, by state, and the actual total apportionments and allocations made from the fund, by state. This is sometimes referred to as a "dollar-in, dollar-out" analysis. Because the contribution data takes about 2 years for FHWA to compile, for our analyses we used data for 4 of 5 years of the SAFETEA-LU period, 2005 through 2008, as data for 2009 were not yet available. The source data are published annually in Highway Statistics and commonly referred to as table FE-221, titled "Comparison of Federal Highway Trust Fund Highway Account Receipts Attributable to the States and Federal-Aid Apportionments and Allocations from the Highway Account." FHWA officials confirmed that it contains the best estimate of state contributions and also contains the total appropriations and allocations received by states from the Highway Account of the fund. We did not independently review FHWA's process for estimating state highway users' contributions into the Highway Trust Fund. However, we have reviewed this process in the past, and FHWA officials verified that they have made changes to the process as a result of that review. In addition, we did not attribute any prior balances in the Highway Trust Fund back to states of origin because these funds are not directly tied to any specific year or state. We only examined the fiscal year 2005 through 2008 period; other time periods could provide a different result. We performed alternative analyses to demonstrate that different methodologies provide different answers to the question of how the contributions of states' highway users compared to the funding states received. Using the same data as described above, we performed a "relative share" analysis, which compared each state's estimated proportion of the total contributions to the Highway Account to each state's proportion of total Federal-Aid Highway funding. We also examined how states fared using FHWA's approach for determining the Equity Bonus Program funding apportionments. We performed this analysis to show the outcomes for states based on the information available at the time the Equity Bonus program apportionments are made. The Equity Bonus program amounts are calculated using the statutory formulas for a subset of Federal-Aid Highway Programs. These include all programs apportioned by formula plus the allocated High Priority Projects. FHWA uses the most current contribution data available at the time it does its estimates. However, as explained above, the time lag for developing this data is about 2 years. Therefore, we applied the contribution data for 2003 through 2007 to the funding data for 2005 through 2009, the full SAFETEA- LU period. For these data, we (1) analyzed the total estimated contributions by state divided by the total funding received by state--the dollar-in, dollar out methodology--and (2) a comparison of the share of contributions to share of payments received for each state. We obtained data from the FHWA Office of Budget for the analysis of state dollar-in dollar-out outcomes, and state relative share data for the Equity Bonus Program. We completed our analyses across the total years of the SAFETEA-LU period, 2005 through 2009. We interviewed FHWA officials and obtained additional information from FHWA on the steps taken to ensure data reliability and determined the data were sufficiently reliable for the purposes of this report To determine the provisions in place during the SAFETEA-LU period to address rate-of-return issues across states and how they affected the highway funding states received, we reviewed SAFETEA-LU legislation, reports by the Congressional Research Service (CRS) and FHWA. We also spoke with FHWA and DOT officials to get their perspectives. We also conducted an analysis of FHWA data on the Equity Bonus Program provisions which were created explicitly to address the rate-of-return issues across states. Our analysis compared funding levels distributed to states via apportionment programs and High Priority Projects before and after Equity Bonus Program provisions were applied, and calculated the percentage increase each state received as a result of the Equity Bonus. To determine what additional factors affected the relationship between contributions to the Highway Trust Fund and the funding states receive, we reviewed GAO reports on federal surface transportation programs and the Highway Trust Fund, as well as CRS and FHWA reports, and the report of the National Surface Transportation Infrastructure Financing Commission. In addition, we reviewed FHWA data on the status of the Highway Account of the Highway Trust Fund. We also met with officials from Department of Transportation's Office of Budget and Programs and FHWA to obtain their perspectives on the issue. Currently, FHWA estimates state-based contributions to the Highway Account of the Highway Trust Fund through a process that includes data collection, adjustment, verification, and final calculation of the states' highway users' contributions. FHWA first collects monthly motor fuel use data and related annual state tax data from state departments of revenue. FHWA then adjusts states' data by applying its own models using federal and other data to establish data consistency among the states. FHWA provides feedback to the states on these adjustments and estimates through FHWA Division Offices. Finally, FHWA applies each state's highway users' estimated share of highway fuel usage to total taxes collected nationally to arrive at a state's contribution to the Highway Trust Fund. We did not assess the effectiveness of FHWA's process for estimating the amount of tax funds attributed to each state for this report. According to FHWA officials, data from state revenue agencies is more reliable and comprehensive than vehicle miles traveled data, so FHWA uses state tax information to calculate state contributions. States submit regular reports to FHWA, including a monthly report on motor-fuel consumption due 90 days after month's end, and an annual motor-fuel tax receipts report due 90 days after calendar year's end. States have a wide variety of fuel tracking and reporting methods, so FHWA adjusts the data to achieve uniformity. FHWA analyses and adjusts fuel usage data, such as off-highway use related to agriculture, construction, industrial, marine, rail, aviation and off-road recreational usage. It also analyzes and adjusts use data based on public-sector use, including federal civilian, and state, county, and municipal use. FHWA headquarters and Division Offices also work together to communicate with state departments of revenue during the attribution estimation process. According to FHWA officials, each year FHWA headquarters issues a memo prompting its Division Offices to have each state conduct a final review of the motor fuel gallons reported by their respective states. FHWA division offices also are required to assess their state's motor fuel use and highway tax receipt process at least once every 3 years to determine if states are complying with FHWA guidance on motor fuel data collection. Once the data are finalized, FHWA applies each state's estimated share of taxed highway fuel use to the total taxes collected to arrive at a state's contribution in the following manner. Finalized estimations of gallons of fuel used on highways in two categories--gasoline and special fuels-- allow FHWA to calculate each state's share of the total on-highway fuel usage. The shares of fuel use for each state are applied to the total amount of taxes collected by the Department of the Treasury in each of the 10 categories of highway excise tax. The state's gasoline share is applied to the gasoline and gasohol taxes, and the state's special fuels share, which includes diesel fuel, is applied to all other taxes, including truck taxes. In addition to the contact named above, Steve Cohen (Assistant Director), Robert Ciszewski, Robert Dinkelmeyer, Brian Hartman, Bert Japikse, Josh Ormond, Amy Rosewarne, and Swati Thomas made key contributions to this report.

Summary:
Federal funding for highways is provided to the states mostly through a series of grant programs known as the Federal-Aid Highway Program, administered by the Department of Transportation's (DOT) Federal Highway Administration (FHWA). In 2005, the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU) authorized $197.5 billion for the Federal-Aid Highway Program for fiscal years 2005 through 2009. The program operates on a "user pay" system, wherein users contribute to the Highway Trust Fund through fuel taxes and other fees. The distribution of funding among the states has been a contentious issue. States that receive less than their highway users contribute are known as "donor" states and states that receive more than their highway users contribute are known as "donee" states. GAO was asked to examine for the SAFETEA-LU period (1) how contributions to the Highway Trust Fund compared with the funding states received, (2) what provisions were used to address rate-of-return issues across states, and (3) what additional factors affect the relationship between contributions to the Highway Trust Fund and the funding states receive. To conduct this review, GAO obtained and analyzed data from FHWA, reviewed FHWA and other reports, and interviewed FHWA and DOT officials. DOT reviewed a draft of this report and provided technical comments, which we incorporated as appropriate. Since 2005, every state received as much or more funding for highway programs than they contributed to the Highway Account of the trust fund. This was possible because more funding was authorized and apportioned than was collected from the states and the fund needed to be augmented with general revenues. If the percentage of funds states contributed to the total is compared with the percentage of funds states received (i.e., relative share), then 28 states received a relatively lower share and 22 states received a relatively higher share than they contributed. Thus, depending on the method of calculation, the same state can appear to be either a donor or donee state. The Equity Bonus Program was used to address rate-of-return issues. It guaranteed a minimum return to states, providing them about $44 billion. Nearly all states received Equity Bonus funding and about half received a significant increase, at least 25 percent, over their core funding. The infusion of general revenues into the Highway Trust Fund affects the relationship between funding and contributions, as a significant amount of highway funding is no longer provided by highway users. Since fiscal year 2008, Congress has transferred nearly $30 billion of general revenues to address shortfalls in the highway program when more funding was authorized than collected. Using rate of return as a major factor in determining highway funding poses challenges to introducing a performance and accountability orientation into the highway program; rate-of-return calculations in effect override other considerations to yield a largely predetermined outcome--that of returning revenues to their state of origin. Because of these and other challenges, funding surface transportation programs remains on GAO's High-Risk list.