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United States General Accounting Office: 
GAO: 

Testimony: 

Before the Subcommittee on Highways and Transit Committee on 
Transportation and Infrastructure, U.S. House of Representatives: 

Not to be Released Before 2:00 p.m. EST: 
Wednesday, March 20, 2002: 

Highway Financing: 

Factors Affecting Highway Funding Fluctuations and Revenue Trends: 

Statement of JayEtta Z. Hecker: 
Director, Physical Infrastructure Issues: 

GAO-02-527T: 

Mr. Chairman and members of the subcommittee: 

We appreciate the opportunity to provide testimony on important Highway
Trust Fund issues. Our statement today is based on our recent reports, 
our ongoing work on the impact of alternative and replacement fuels on 
the Highway Trust Fund, and our review of the fiscal year 2003 Revenue
Aligned Budget Authority adjustment.[Footnote 1] As you know, the 
Highway Trust Fund is the principal mechanism for funding federal 
highway programs authorized by the Transportation Equity Act for the 
21st Century (TEA-21). TEA-21 “guaranteed” specific annual funding 
levels for most highway programs on the basis of projected receipts to 
the Highway Trust Fund and provided for annual adjustments to these 
funding levels based on actual receipts and revised projections of 
trust fund revenue. These adjustments are referred to as the Revenue 
Aligned Budget Authority or RABA. In fiscal year 2003, for the first 
time, the RABA adjustment is negative—decreasing the guaranteed level 
of highway funding by $4.369 billion. Consequently, the highway 
funding level for fiscal year 2003 will be over $8 billion lower than 
the fiscal year 2002 level. 

Concerned about the significant drop in highway funding due to the RABA
adjustment, you asked us to assess the fiscal year 2003 RABA 
calculation. Additionally, you expressed concerns about the amount of 
future revenue forgone by the Highway Trust Fund due to gasohol usage 
and asked about ways to increase revenues into the trust fund. In 
response, our statement discusses (1) the reasonableness of the fiscal 
year 2003 RABA calculation; (2) the $600 million error in the initial 
RABA adjustment released by the administration; (3) the impact of 
gasohol usage on the Highway Trust Fund; and (4) ways to reduce 
fluctuations in the RABA adjustment and industry proposals to increase 
Highway Trust Fund revenue. (See appendix I for information on our 
objectives, scope, and methodology.) 

In summary: 

* The fiscal year 2003 RABA calculation appears reasonable based on the
information we reviewed. While the RABA adjustment is clearly severe, 
it largely is a reflection of the multiple ways a downturn in the 
economy affects the calculation. The RABA calculation consists of 
“look back” and “look ahead” components. About 80 percent of the 
fiscal year 2003 RABA adjustment is attributable to the “look back” 
portion of the RABA calculation, which compares the actual Highway 
Account receipts for fiscal year 2001 to the projections of receipts 
for fiscal year 2001 included in TEA-21 plus an adjustment for the 
RABA calculation made for that year. Our review shows that the amounts 
distributed to the Highway Trust Fund for the first 9 months of fiscal 
year 2001 were reasonable and adequately supported on the basis of 
available information. The remaining 20 percent of the fiscal year 
2003 RABA adjustment is due to the “look ahead” portion of the 
calculation, which compares the Department of Treasury’s (Treasury) 
projection of Highway Account receipts for fiscal year 2003 with the 
projection of receipts for that year contained in TEA-21. Although we 
did not independently evaluate the methodology and the economic models 
Treasury used to develop its revenue projections, our review of a 
qualitative description of the process, key inputs, and changes to the
models gave us no reason to question the resulting projections. 
Similarly, our comparison of projections prepared by Treasury and the
Congressional Budget Office (CBO) did not lead us to question the
projections used for the fiscal year 2003 RABA calculation. 

* In late January 2002, the administration announced that the fiscal 
year 2003 RABA adjustment would be a negative $4.965 billion. Within a 
few days of the announcement, the administration reported that an 
error had been made and that the correct amount was a negative $4.369 
billion—a $600 million difference. The error occurred in Treasury’s 
allocation of projected highway tax revenues to the various accounts 
that receive them, rather than in Treasury’s economic models for 
projecting such revenues. Treasury did not detect the error until 
after the RABA adjustment had been released to the public and the 
Federal Highway Administration (FHWA) had made its initial 
calculations for distributing funds to the states. Treasury is taking 
steps to improve its internal controls in order to prevent this type 
of error from occurring again. 

* The use of ethanol blended fuel (gasohol) instead of gasoline reduces
Highway Trust Fund revenue because it is partially exempt from the
standard excise tax on gasoline (18.4 cents) and 2.5 cents of the tax
received on each gallon of gasohol sold is transferred to the General 
Fund.[Footnote 2] Based on our ongoing work, our preliminary estimates 
show that the Highway Account did not receive about $6.01 billion (in 
constant 2001 dollars) from fiscal years 1998 through 2001 due to 
these tax provisions. Further, gasohol use is projected to increase 
and thus the impact of these tax provisions will grow as well. Using 
Treasury’s projections of gasohol tax receipts, we estimate that the 
Highway Account will forgo an additional $13.72 billion (in constant 
2001 dollars) due to the partial tax exemption from fiscal years 2002 
through 2012. We also estimate that the Highway Trust Fund will forgo 
about $6.92 billion from fiscal years 2002 to 2012 due to the General 
Fund transfer (in constant 2001 dollars).[Footnote 3] According to 
Department of Agriculture (USDA) and ethanol industry officials, the 
partial tax exemption for gasohol helps to create a demand for ethanol 
and make gasohol price competitive with gasoline. 

* There are several ways the RABA adjustment could be changed to help
reduce fluctuations in highway funding. For example, the RABA
adjustment could be distributed over 2 years. In addition, industry 
groups have proposed a number of ways to increase Highway Trust Fund
revenues. Ultimately, however, the Congress and the administration must
weigh the advantages and disadvantages of these and other ways to
stabilize highway funding and/or increase Highway Trust Fund revenues. 

Background: The Highway Trust Fund and TEA-21: 

The Highway Revenue Act of 1956 established the Highway Trust Fund as
an accounting mechanism to help finance federal highway programs. In
1983, the Highway Trust Fund was divided into two accounts: a Highway
Account and a Mass Transit Account. Receipts to the Highway Account are
used to fund highway programs, through which billions of dollars are
distributed to the states annually for the construction and repair of
highways and related activities. Treasury uses a revenue allocation and
reporting process to distribute highway user taxes to the Highway Trust
Fund. 

Financing for the Highway Trust Fund is derived from a variety of 
federal highway user taxes including excise taxes on motor fuels 
(gasoline, gasohol, diesel, and special fuels) and tires, sales of new 
trucks and trailers, and the use of heavy vehicles. As table 1 shows, 
the excise tax rates and distribution of the tax revenues vary. The 
different tax rates reflect federal policy decisions. For example, in 
the 1970s and 1980s, the federal government adopted numerous policies 
to encourage the use of alternatives to imported fossil fuels and help 
support farm incomes. Among these policies were tax incentives that 
targeted the use of alcohol fuels derived from biomass materials, such 
as ethanol.[Footnote 4] Ethanol blended fuels (gasohol) are partially 
exempt from the standard excise tax on gasoline (18.4 cents). The 
proportion of ethanol contained in each gallon of fuel determines the 
size of the partial exemption. The most common ethanol blend contains 
90 percent gasoline and 10 percent ethanol and is currently taxed at 
13.1 cents per gallon—an exemption of 5.3 cents.[Footnote 5] The 
federal government also uses the distribution of excise tax receipts 
to different accounts to achieve policy goals. For example, a small 
part of the excise tax on most motor fuels is distributed to the 
Leaking Underground Storage Tank Trust Fund to clean-up contamination 
caused by underground storage tanks. Additionally, 2.5 cents of the 
tax received on each gallon of gasohol is transferred to the General 
Fund, rather than the Highway Trust Fund, for deficit reduction 
purposes. 

Table 1: Excise Tax Rates and Distributions of Highway User Taxes, as 
of July 2001 (Cents per gallon): 

Type of tax: Motor fuels taxes: 

Gasoline: 
Tax rate: 18.40; 
Distribution of tax: Highway Trust Fund: Highway Account: 15.44; 
Distribution of tax: Highway Trust Fund: Transit Account: 2.86; 
Leaking Underground Storage Tank Trust Fund: 0.10; 
General Fund: [Empty]. 

Diesel: 
Tax rate: 24.40; 
Distribution of tax: Highway Trust Fund: Highway Account: 21.44; 
Distribution of tax: Highway Trust Fund: Transit Account: 2.86; 
Leaking Underground Storage Tank Trust Fund: 0.10; 
General Fund: [Empty]. 

Type of tax: Alternative fuels taxes: 

Gasohol (10% ethanol):
Tax rate: 13.10; 
Distribution of tax: Highway Trust Fund: Highway Account: 7.64; 
Distribution of tax: Highway Trust Fund: Transit Account: 2.86; 
Leaking Underground Storage Tank Trust Fund: 0.10; 
General Fund: 2.5. 

Alternative fuels taxes: Liquefied petroleum gas; 
Tax rate: 13.60; 
Distribution of tax: Highway Trust Fund: Highway Account: 11.47; 
Distribution of tax: Highway Trust Fund: Transit Account: 2.13; 
Leaking Underground Storage Tank Trust Fund: [Empty]; 
General Fund: [Empty]. 

Alternative fuels taxes: Liquefied natural gas; 
Tax rate: 11.90; 
Distribution of tax: Highway Trust Fund: Highway Account: 10.04; 
Distribution of tax: Highway Trust Fund: Transit Account: 1.86; 
Leaking Underground Storage Tank Trust Fund: [Empty]; 
General Fund: [Empty]. 

Alternative fuels taxes: M85 (from natural gas); 
Tax rate: 9.25; 
Distribution of tax: Highway Trust Fund: Highway Account: 7.72; 
Distribution of tax: Highway Trust Fund: Transit Account: 1.43; 
Leaking Underground Storage Tank Trust Fund: 0.10; 
General Fund: [Empty]. 

Alternative fuels taxes: Compressed natural gas (cents per thousand 
cu. ft.); 
Tax rate: 48.54; 
Distribution of tax: Highway Trust Fund: Highway Account: 38.83; 
Distribution of tax: Highway Trust Fund: Transit Account: 9.70; 
Leaking Underground Storage Tank Trust Fund: [Empty]; 
General Fund: [Empty]. 

Type of tax: Truck-related taxes: 

Tires: 
Tax rate: 0-40 lbs, no tax
Over 40 lbs – 70 lbs, 15 cents per pound in excess of 40;
Over 70 lbs – 90 lbs, $4.50 plus 30 cents per pound in excess of 70;
Over 90 lbs, $10.50 plus 50 cents per pound in excess of 90. 

Truck and Trailer Sales Tax: 
Tax rate: 12 percent of retailer’s sales price for tractors and trucks 
over 33,000 lbs gross vehicle;
weight (GVW) and trailers over 26,000 lbs GVW. 

Heavy Vehicle Use Tax; 
Tax rate: Annual tax:
Trucks 55,000 lbs and over GVW, $100 plus $22 for each 1,000 lbs (or 
fraction thereof) in excess of 55,000 lbs (maximum tax of $550). 

Note: Tax rates for gasohol mixtures vary according to the amount of 
ethanol contained in the mixture. 

Source: FHWA and Treasury. 

[End of table] 

TEA-21 continued the use of the Highway Trust Fund as the mechanism
for accounting for federal highway user taxes. TEA-21 also established
guaranteed spending levels for certain highway and transit programs. 
Prior to TEA-21, these programs competed for budgetary resources 
through the annual appropriations process with other domestic 
discretionary programs. New budget categories were established for 
highway and transit spending, effectively establishing a budgetary “
firewall” between those programs and other domestic discretionary 
spending programs. Of the $217.9 billion authorized for surface 
transportation programs over the 6-year life of TEA-21, about $198 
billion is protected by the budgetary firewall—about $162 billion for 
highway programs and $36 billion for transit programs. 

Under TEA-21, the amount of highway program funds distributed to the
states is tied to the amount of actual tax receipts credited to the 
Highway Account of the Highway Trust Fund. TEA-21 guaranteed specific 
levels of funding for highway programs from fiscal year 1999 through 
fiscal year 2003, on the basis of projected receipts of the Highway 
Account. TEA-21 also provided that beginning in fiscal year 2000, this 
guaranteed funding level for each fiscal year would be adjusted upward 
or downward through the RABA calculation as the levels of Highway 
Account receipts increased or decreased. To determine the RABA 
adjustment, the Office of Management and Budget and the Office of the 
Secretary in the Department of Transportation rely on information on 
Highway Account receipts and revised Highway Account projections 
supplied by Treasury. Specifically, the Bureau of Public Debt provides 
the actual Highway Account receipts for the prior fiscal year, and the 
Office of Tax Analysis (OTA) provides a projection of Highway Account 
receipts for the next fiscal year. 

The Calculation of the Fiscal Year 2003 RABA Adjustment Appears 
Reasonable: 

On the basis of the information we reviewed, the fiscal year 2003 RABA
calculation—a negative $4.369 billion—appears reasonable. The RABA
adjustment for fiscal year 2003 was calculated by (1) comparing the 
actual Highway Account receipts for fiscal year 2001 to the 
projections of receipts for fiscal year 2001 included in TEA-21, and 
an adjustment for the RABA calculation made for that year (the look 
back portion of the calculation) and (2) comparing projections of 
Highway Account receipts for fiscal year 2003 with the projection of 
these receipts contained in TEA-21 (the look ahead portion of the 
calculation). The sum of these differences is the RABA adjustment. 
Table 2 shows the RABA calculations for fiscal years 2000 through 
2003. As shown, the RABA adjustments for fiscal year 2000 through 
fiscal year 2002 were positive—increasing highway funding levels by a 
total of over $9 billion. However, the RABA adjustment for fiscal year 
2003 is negative $4.369 billion. 

Table 2: RABA Calculation for Fiscal Years 2000 through 2003 (In 
millions of dollars): 

Fiscal year: FY 2000; 
"Look back": 
1998 actual Highway Account receipts: $23,135; 
less: 1998 TEA-21 estimated Highway Account receipts: $22,164; 
less: look-ahead result for 1998: $0; 
subtotal: $971. 
"Look ahead": 
2000 estimated Highway Account receipts: $28,551; 
less: 2000 TEA-21 estimated Highway Account receipts $28,066; 
subtotal: $485; 
RABA: $1,456. 

Fiscal year: FY 2001; 
"Look back": 
1999 actual Highway Account receipts: $33,815; 
less: 1999 TEA-21 estimated Highway Account receipts: $32,619; 
less: look-ahead result for 1999: $0; 
subtotal: $1,196; 
"Look ahead": 
2001 estimated Highway Account receipts: $30,368; 
less: 2001 TEA-21 estimated Highway Account receipts: $28,506; 
subtotal: $1,862; 
RABA: $3,058. 

Fiscal year: FY 2002; 
"Look back": 
2000 actual Highway Account receipts: $30,334; 
less: 2000 TEA-21 estimated Highway Account receipts: $28,066; 
less: look-ahead result for 2000: $485; 
subtotal: $1,783; 
"Look ahead": 
2002 estimated Highway Account receipts: $31,732; 
less: 2002 TEA-21 estimated Highway Account receipts: $28,972; 
subtotal: $2,760; 
RABA: $4,543 

Fiscal year: FY 2003; 
"Look back": 
2001 actual Highway Account receipts: $26,900; 
less: 2001 TEA-21 estimated Highway Account receipts: $28,506; 
less: look-ahead result for 2001: $1,862; 
subtotal: ($3,468); 
"Look ahead": 
2003 estimated Highway Account receipts: $28,570; 
less: 2003 TEA-21 estimated Highway Account receipts: $29,471; 
subtotal: ($901); 
RABA: ($,369). 

Note: Actual receipts reflect certified net tax receipts (excluding 
fines and penalties) after deduction of transfers and refunds for the 
first three quarters of the fiscal year plus an estimate for the fourth
quarter. To account for the differences between actual and estimated 
receipts for the previous year’s fourth quarter, Treasury makes an 
adjustment to the current fiscal year’s receipts. Treasury prepares
forecasts of tax receipts to the Highway Account of the Highway Trust 
Fund for the president’s budget and other analyses. The Congressional 
Budget Office prepared the estimates of Highway Account receipts 
contained in TEA-21. 

Source: GAO analysis. 

[End of table] 

Eighty percent of the fiscal year 2003 RABA adjustment is attributable 
to the look back portion of the calculation. The actual fiscal year 2001
Highway Account receipts were about $1.6 billion lower than projections
in TEA-21. According to Treasury, actual fiscal year 2001 receipts were
lower than expected due to the slowdown in the economy, which 
especially affected heavy truck sales, and increased gasohol use. We
reviewed the amounts distributed to the Highway Trust Fund for the 
first 9 months of fiscal year 2001, and concluded that these amounts 
were reasonable and adequately supported on the basis of available
information. With respect to the look ahead portion of the 
calculation, we reviewed Treasury’s process for projecting Highway 
Account revenues. Although we did not independently evaluate the 
methodology and the economic models Treasury used to develop its 
revenue projections, our review of a qualitative description of the 
process, key inputs, and changes to the models gave us no reason to 
question the resulting projections. 

Treasury’s Excise Tax Distributions to the Highway Trust Fund for the 
First 9 Months of Fiscal Year 2001 Are Reasonable: 

The Secretary of the Treasury transfers applicable excise tax receipts,
including receipts from gasoline and other highway taxes, from the
General Fund to the excise tax related trust funds, including the 
Highway Trust Fund, on a monthly basis. These transfers are based on 
estimates because actual data on which to base the allocations are not 
available when the deposits are initially made. OTA prepares these 
estimates on the basis of historical IRS certification data and actual 
excise tax revenue collections. Subsequently, IRS certifies the actual 
excise tax revenue collections that should have been distributed to 
the trust funds on the basis of tax returns and payment data.[Footnote 
6] Using the IRS certifications, Treasury makes quarterly adjustments 
to the initial trust fund distributions. For example, in March 2001, 
Treasury made an adjustment to decrease the fiscal year 2001 excise 
tax revenue distributions to the Highway Trust Fund to correct for 
actual collections in the fourth quarter of fiscal year 2000. The 
certified fourth quarter receipts were $1.2 billion less than the 
amount initially distributed on the basis of OTA’s estimates for that 
quarter. According to an OTA official, OTA had calculated the original 
estimated transfer amounts for the quarter using an economic model 
that assumed a higher rate of economic growth through calendar year 
2000 than was actually the case.[Footnote 7] As a result, the downward 
adjustment was made, reducing the fiscal year 2001 distributions to 
the Highway Trust Fund by $1.2 billion, which contributed to the 
fiscal year 2003 negative RABA adjustment.[Footnote 8] 

Our past reports have identified errors and problems with Treasury’s
excise tax allocation process.[Footnote 9] However, Treasury has made 
and continues to make improvements to this process. On February 11, 
2002, we issued a report on the results of procedures we performed 
related to the distributions of excise tax revenue to the Highway 
Trust Fund in fiscal year 2001.[Footnote 10] On the basis of this 
work, we believe the amounts distributed to the Highway Trust Fund for 
the first 9 months of fiscal year 2001, which were subject to IRS’ 
quarterly excise tax certification process and which were adjusted on 
the basis of this process, were reasonable and were adequately 
supported according to available information. Additionally, we believe 
the March 2001 adjustment made by Treasury to reduce fiscal year 2001 
excise tax distributions to the Highway Trust Fund by $1.2 billion
was reasonable and adequately supported. 

IRS expects to deliver the results of its certifications for 
distributions of excise tax revenue collected during the period July 
1, 2001, through September 30, 2001 to Treasury’s Financial Management 
Service by March 20, 2002. Consequently, the distributions of fourth 
quarter fiscal year 2001 excise tax revenue were based solely on 
estimates prepared by OTA. We did not draw any conclusions about the 
reasonableness of the distributions made to the Highway Trust Fund for 
the fourth quarter of fiscal year 2001. 

Fiscal Year 2001 Receipts Lower Than Expected: 

One component of the look back portion of the RABA calculation is the
comparison of actual fiscal year 2001 Highway Account receipts with
projections of those receipts in TEA-21. The actual receipts were about
$1.6 billion lower than the amounts contained in TEA-21. According to
Treasury, the lower than expected highway excise tax receipts in fiscal
year 2001 were due to several factors. Most importantly, the weakened
economy contributed to a decline in highway excise taxes paid. All but 
one of the Highway Trust Fund receipt sources were lower in fiscal 
year 2001 than 2000. For example, tax revenue from the retail tax on 
trucks dropped 55 percent from fiscal year 2000 to fiscal year 2001. 
It is important to note that the tax is applied to the sale of new 
trucks only. As the economy weakened, large numbers of used trucks 
were placed on the market, which depressed prices and sales in the new 
heavy truck market. 

In addition to the economic downturn, the rise in the use of gasohol
contributed to decreased Highway Account receipts. The amount of
gasohol receipts allocated to the Highway Account rose by 17.5 percent
between fiscal years 2000 and 2001, which Treasury believes is 
evidence of an ongoing substitution of gasohol fuels for gasoline. 
Because gasohol is taxed at a lower rate than gasoline and a portion 
of the tax on gasohol is transferred to the General Fund, increases in 
gasohol use and corresponding reductions in gasoline use decrease 
Highway Account revenues. 

Treasury Uses Seven Economic Models to Forecast Receipts: 

While not the main factor, the look ahead portion of the RABA 
calculation also contributed to the overall negative RABA adjustment. 
As discussed earlier, the look ahead is the difference between TEA-21’
s projections for the next fiscal year to current projections from the 
president’s budget, which are prepared by Treasury. Based on the 
general qualitative description Treasury provided us about its 
methodology and economic models used to develop Highway Trust Fund 
revenue projections, we have no reason to question the projections for 
fiscal year 2003. Treasury generally performs two forecasting 
exercises each year, including one for the president’s budget. 
Treasury uses seven econometric models to forecast each highway excise 
tax revenue source, such as the tax on gasoline. These models seek to 
approximate the relationship between historical tax liability and 
current macroeconomic variables, such as the gross domestic product. 
This estimated relationship is the baseline, and Treasury uses it to 
project future excise tax liability, given current law and the 
administration’s economic assumptions. After calculating future tax
liability, Treasury forecasters convert the tax liability forecast to 
a tax receipts forecast using information on deposit rules, payment 
patterns, and actual collections. 

The administration’s economic assumptions drive the projections made
with each model. According to Treasury, receipts forecasting is a policy
exercise conducted for the president to show the state of the Highway
Trust Fund if the administration’s economic assumptions were to come to
fruition. Consequently, Treasury’s forecasts incorporate economic
assumptions formulated for the budget by the “Troika,” which consists of
the Council of Economic Advisors, the Office of Management and Budget,
and Treasury. Because the goal is to provide a forecast consistent with
these economic assumptions, the models use these assumptions directly
as explanatory variables, or link other explanatory variables to the
assumptions provided. Several of the administration’s economic
assumptions are publicly available, such as the gross domestic product
and consumer price index. However, most Troika assumptions are not
publicly available. Other variables specific to the Highway Trust Fund 
are included in the economic models. Treasury generally obtains this
information from other federal agencies. For example, Treasury
incorporates USDA’s forecast of ethanol use in its gasohol model.
However, according to Treasury, the forecasters must ensure that the 
addition of these other variables does not create inconsistencies 
between the projections and the administration’s assumptions. 

It should also be noted that Treasury does not try to predict future
regulatory or legislative changes at the federal or state levels that 
could affect Highway Trust Fund revenue but bases its projections on 
current law. Any legislative or regulatory changes that affect Highway 
Trust Fund revenue will affect the accuracy of the forecasts. Treasury 
continuously updates its models to incorporate legislative, economic, 
and other relevant changes—which are then reflected in the next 
forecasting exercise. 

Treasury’s Highway Trust Fund Forecasting Framework Has Remained
Consistent: 

According to Treasury officials, Treasury’s modeling framework for
projecting highway excise tax receipts has not changed in recent years.
Treasury’s framework consists of a series of econometric models that
approximate the relationship between historical tax liability and 
current macroeconomic variables, which are then used to project future 
tax liability given current law and certain economic assumptions. 
Although the overall framework has remained consistent, Treasury 
officials noted that the specific economic models used to project 
receipts are continuously evolving to reflect current circumstances. 
For example, the models are constantly updated to incorporate the most 
current information on tax collections and reported tax liabilities, 
as well as enacted legislation. In addition to these routine changes, 
the models have occasionally undergone other modifications. Treasury 
identified 15 major changes to the models since 1998. These changes 
ranged from moving the highway-type tire tax from an annual model to a 
quarterly model and revising the ethanol forecast in the gasohol model 
to reflect the phasing out of methyl tertiary-butyl ether (MTBE) in 
certain states. According to Treasury, the identified changes were 
designed to improve the models’ forecasting ability. 

Although Treasury does not use an independent reviewer to validate the
models, Treasury officials noted several ways they validate them. First,
the Director of Treasury’s Office of Tax Analysis reviews the results 
of the model for accuracy and soundness at least twice a year. Second, 
Treasury officials compare the projected receipts with actual receipts 
to assess the validity of the models. In comparing the projected and 
actual receipts, Treasury forecasters try to determine the cause of 
any substantial differences and make changes to the model, as 
appropriate. Third, trust fund agencies, such as FHWA, receive the 
forecasts semiannually and may offer comments to Treasury on the 
projections.[Footnote 11] 

Treasury’s Current Projections Are Similar to CBO’s Forecast: 

In order to help determine the reasonableness of Treasury’s 
projection, we compared it with CBO’s forecasts. This comparison does 
not raise any questions about the reasonableness of Treasury’s 
projections. For example, despite different methodologies and 
assumptions, Treasury and CBO projections of Highway Account receipts 
for the budget window are very similar. (See figure) Both agencies 
forecast steady growth in receipts from fiscal years 2002 through 
2012. For example, both Treasury and CBO project the average annual 
growth of highway-related excise taxes will be about 3 percent. 

Figure 1: Comparison of Treasury and CBO Projections of Highway Account
Receipts, 2002 to 2012: 

[Refer to PDF for image: line graph] 

This graph depicts the Treasury and CBO Projections of Highway Account
Receipts, from fiscal year 2002 to fiscal year 2012. 

Both projections show an increase in receipts from approximately $28 
billion in 2002 to approximately $38 billion in 2012. 

Source: Treasury and CBO. 

[End of figure] 

$600 Million Error in RABA Adjustment Occurred Outside of Treasury’s 
Models: 

In January 2002, the administration announced that the fiscal year 2003
RABA adjustment would be a negative $4.965 billion. The administration
subsequently announced that an error had been made in calculating the
RABA adjustment and that the correct amount was a negative $4.369
billion—a $600 million difference. 

The error, which was made in Treasury’s allocation of projected highway
tax revenues to various accounts rather than in its economic models,
affected the look ahead part of the fiscal year 2003 RABA calculation.
Specifically, it occurred in Treasury’s allocation of projected revenues
from gasohol sales to the General Fund, the Leaking Underground Storage
Tank Trust Fund, and the Highway and Transit Accounts within the
Highway Trust Fund. In short, the error resulted in the incorrect
distribution of projected gasohol receipts among the funds. 

Because gasohol has six different blends—all with different tax rates 
and distributions—the gasohol allocations are complicated and require 
many “links” among several spreadsheets. With respect to gasohol, the 
Highway Account receipts are calculated after allocations for the 
other accounts—the Mass Transit Account, the Leaking Underground 
Storage Tank Trust Fund, and the General Fund—have been calculated. 
This is because the Highway Account is a “catch-all” for taxes not 
already attributed to other accounts. A misalignment occurred between 
the different spreadsheets used to distribute gasohol tax revenues to 
the different accounts, which caused too much of the gasohol revenues 
to be transferred to the General Fund. Therefore, the error 
incorrectly lowered projected Highway Account revenue beginning with 
fiscal year 2002. 

According to a Treasury official, a number of factors contributed to the
error, including tightened time constraints during this budget cycle for
Treasury forecasters to calculate and review their projections for the 
fiscal year 2003 budget. Each forecaster is responsible for reviewing 
his/her own calculations. In hindsight, however, this official said 
that the internal quality checks his office made were insufficient, 
especially on the gasohol calculations, which are very complex. He 
noted that Treasury plans to take several steps to avoid such an error 
in the future, including requiring another Treasury forecaster to spot 
check the projections. 

Gasohol Usage Has Significant Impact on Trust Fund: 

The use of gasohol instead of gasoline affects the amount of Highway
Account revenue for two reasons. First, gasohol is partially exempt from
the standard gasoline excise tax. Second, 2.5 cents of the tax 
received on each gallon of gasohol sold is transferred to the General 
Fund. (See figure 2.) Based on our ongoing work, our preliminary 
estimates show that the partial tax exemption resulted in $3.86 
billion in revenue forgone by the Highway Account during fiscal years 
1998 through 2001.[Footnote 12] We also estimate that the General Fund 
transfer caused a reduction of $2.15 billion in Highway Account 
revenue during the same period. 

Figure 2: Distribution of Gasoline and Gasohol Taxes to Different 
Accounts: 

[Refer to PDF for image: two pie-charts] 

Gasoline: 18.4 cents: 
Highway account: 15.44 cents; 
Mass Transit account: 2.86 cents; 
Leaking Underground Storage Tank Trust Fund: 0.1 cents. 

Gasohol: 13.1 cents: 
Highway account: 7.64 cents; 
Mass Transit account: 2.86 cents; 
Leaking Underground Storage Tank Trust Fund: 2.5 cents. 

Source: GAO analysis. 

[End of figure] 

Treasury projects that gasohol use will continue to rise steadily 
through fiscal year 2012. According to Treasury, such an increase will 
occur at the expense of gasoline as some states ban the use of MTBE as 
an oxygenate additive. Using Treasury’s highway excise tax revenue 
projections, we estimate that the partial tax exemption will lower 
Highway Account revenue by a total of $13.72 billion from fiscal years 
2002 through 2012. (See figure 3.) We also estimate that the Highway 
Account will not receive $2.36 billion due to the General Fund 
transfer from fiscal years 2002 through 2005, when the transfer ends. 
[Footnote 13] In addition, if the amount of the transfer is not 
dedicated to the Highway Account following fiscal year 2005, we 
project that the Highway Account will forgo $4.56 billion from fiscal 
years 2006 through 2012. State or federal legislation or regulations
that result in gasohol use above what is currently projected, such as a 
nationwide ban on MTBE, would increase the negative impact on the
Highway Account absent other changes. 

Figure 3: Estimated Revenue Forgone by the Highway Account Due to 
Gasohol Tax Provisions, 1998 to 2012: 

[Refer to PDF for image: stacked vertical bar graph] 

The graph depicts estimated revenue forgone by the Highway Account due 
to gasohol tax provisions from 1998 to 2012. The following are 
depicted: 

General Fund transfer; 
Partial tax exemption. 

Note: Estimates for fiscal years 1998 to 2000 are based on actual 
excise taxes collected. We estimated fiscal year 2001 receipts using 
actual receipts collected for the first three quarters and a 
projection of receipts collected for the fourth quarter. Estimates for 
fiscal years 2002 to 2012 are based on Treasury’s projections. 
Estimates are in constant 2001 dollars. 

Source: GAO analysis. 

[End of figure] 

According to USDA and ethanol industry officials, the partial tax
exemption for gasohol is intended to create a demand for ethanol that 
will raise the price of ethanol at least to the point where producers 
can cover costs. These officials stated that if the partial tax 
exemption on ethanol was removed, the price of ethanol would no longer 
be competitive with gasoline and the demand would disappear. In this 
case, ethanol fuel production would, for the most part, not continue. 
Furthermore, ethanol industry officials we talked to warned that 
because a substantial amount of the corn grown in the United States is 
used for ethanol, the collapse of the ethanol industry would affect 
the corn and agriculture markets which could in turn affect the 
federal government’s agricultural support payments. 

Ways to Reduce Highway Funding Fluctuations and Industry Proposals to
Increase Revenues: 

As the Congress considers the reauthorization of surface transportation
programs, there are several ways it could restructure the RABA 
adjustment to reduce fluctuations in highway funding. Furthermore,
industry officials have identified a number of possible ways to increase
Highway Trust Fund revenues. Ultimately, the Congress and the 
administration must weigh the advantages and disadvantages of changing
the RABA adjustment and/or Highway Trust Fund revenue streams. The
discussion that follows is not intended to show support for any possible
alternatives but instead to describe some of the ways highway funding
could be increased. 

The RABA formula as defined by TEA-21 contains look back and look
ahead components that tend to accentuate the impact of any shifts in
Highway Account receipts. For example, the recent downturn in the
economy is reflected in several elements of the fiscal year 2003 RABA
calculation. First, the actual receipts for fiscal year 2001 were 
lower than expected. Second, the downturn caused a need to correct for 
optimistic projections of fiscal year 2001 receipts made in December 
1999. Third, the fiscal year 2003 projections are lower than those 
contained in TEA-21 because the updated projections reflect the 
current economic conditions. 

There are several changes that could be made to reduce the potential for
dramatic swings in funding for highway programs but maintain a tie to
actual receipts credited to the Highway Account. For example, changes to
the RABA adjustment that could smooth out the impact of significant
funding changes would include (1) eliminating the look ahead part of the
RABA calculation, (2) averaging the look back part of the calculation 
over 2 years, and (3) distributing the RABA adjustments over 2 years. 
In figure 4, we show the actual RABA adjustments under the current 
structure and the adjustments that would have been made using these 
three options from fiscal years 2000 through 2003. 

Figure 4: Comparison of Different RABA Options (Dollars in millions): 

[Refer to PDF for image: multiple line graph] 

The graph depicts the following for the period of 2000 through 2003: 
Current; 
Eliminating the look ahead; 
Distributing adjustment over 2 years; 
Using 2-year average for look back. 

Source: GAO analysis. 

[End of figure] 

As shown, the three options appear to produce less dramatic shifts in
funding than the current RABA mechanism over the past four years.
However, we did not analyze how these options would perform against
different trust fund scenarios or economic cycles in the future. 

Industry groups have proposed various ways to increase Highway Trust
Fund revenue such as crediting the Highway Trust Fund for the interest
earned on its balances, increasing the use of tolls, and/or 
establishing an indexing system to help ensure that gas tax revenues 
are linked to inflation. Although each of these actions would increase 
Highway Trust Fund revenues, we have not evaluated their fiscal or 
public policy implications. 

Another way to enhance Highway Trust Fund revenues would be to
increase highway excise taxes. Although no tax increase is attractive, 
there are some equity arguments that support an increase in certain
highway user taxes. For example, for some time FHWA has reported that
heavy trucks (trucks weighing over 55,000 pounds) cause a
disproportionate amount of damage to the nation’s highways and have not
paid a corresponding share for the cost of the pavement damage they
cause. Currently, heavy vehicles are taxed at the rate of $100 per 
year plus $22 for every 1,000 pounds (or fraction thereof) they weigh 
over 55,000 pounds. However the tax is capped at $550. In 2000, we 
reported that the Joint Committee on Taxation estimated that raising 
the ceiling on this fee to $1900 could generate about $100 million per 
year.[Footnote 14] 

Mr. Chairman, this concludes my prepared remarks. I would be pleased to
answer any questions you or other members of the Subcommittee may
have. For questions regarding this testimony please contact JayEtta Z. 
Hecker on (202) 512-2834 or at heckerj@gao.gov. Individuals making key
contributions to this testimony included Nikki Clowers, Helen
Desaulniers, Mehrzad Nadji, Stephen Rossman, Ron Stouffer, and James
Wozny. 

[End of section] 

Appendix I: Objectives, Scope, and Methodology: 

To determine the reasonableness of the Revenue Aligned Budget Authority
(RABA) calculation we relied in part on previous work done by GAO 
under an agreement with the Department of Transportation’s Inspector
General which resulted in a February 2002 report: Applying Agreed-Upon
Procedures: Highway Trust Fund Excise Taxes (GAO-02-379R). Under that
agreement we (1) performed detailed tests of transactions that represent
the underlying basis of the amounts distributed to the Highway Trust
Fund, (2) reviewed the Internal Revenue Service’s quarterly 
certifications of these amounts, and (3) reviewed the Office of Tax 
Analysis’ process for estimating amounts distributed to the Highway 
Trust Fund in the fourth quarter of fiscal year 2001. We also 
interviewed knowledgeable Department of Treasury, Office of Management 
and Budget, and Department of Transportation officials who provided 
documentation and described the processes used to develop the 
calculation. We obtained from the Treasury’s Office of Tax Analysis 
(OTA) a general description of its economic models, including key 
inputs and changes made to the models since 1998, which are used to 
estimate future Highway Trust Fund revenues. Additionally, we reviewed 
related OTA internal analyses and reports. However, we did not 
evaluate or certify Treasury’s economic models that forecast future 
Highway Trust Fund revenues. We met with Congressional Budget Office 
(CBO) officials who described their process for projecting Highway 
Trust Fund revenues. CBO officials also provided their Highway Trust 
Fund revenue forecast, which we compared to Treasury’s projections. 

To determine how the $600 million error in the initial RABA adjustment
was made, we interviewed Treasury and DOT officials. We also reviewed
Treasury’s workpapers to determine the source and cause of the error. 

To evaluate the impact of gasohol usage on the Highway Account we
interviewed Department of Energy, Transportation and Agriculture
officials and representatives from the Renewable Fuels Association, the
American Road and Transportation Builders Association and the Alliance
of Automobile Manufacturers. We reviewed Department of Energy and
Agriculture reports and analyses on ethanol production and consumption.
To calculate the revenue forgone to the Highway Trust Fund as a result 
of the gasohol tax provisions we used a methodology we developed in a 
prior study of alcohol fuel tax incentives.[Footnote 15] In 
particular, we used actual and projected excise tax receipts on 
gasohol and gasoline used for gasohol; tax rates for gasohol, gasoline 
used for gasohol, and gasoline; and information on the distribution of 
the receipts from these fuels to the Highway Account, Mass Transit 
Account, the Leaking Underground Storage Tank Trust Fund, and General 
Fund to calculate the revenue forgone by the Highway Account due to 
gasohol tax provisions. Our data sources included the Statistics of 
Income Bulletin and Treasury’s latest projections of gasohol tax 
receipts and refunds and credits. In addition, Treasury provided 
information on the tax rates and the distributions of the tax receipts 
to different accounts by year. Our estimates of the future impact
of gasohol use are based on Treasury’s projections of gasohol tax 
receipts and as a result, our projections incorporate the same 
assumptions used by Treasury. 

The estimates that we present are “static” estimates in that they do not
take into account the potential changes in motor fuel consumption in
response to the elimination of the exemptions. The projections do not
represent the amount of revenue that would be saved if the exemptions
were eliminated because they do not account for the behavioral responses
that might alter the total consumption in the future. Rather, the 
estimates that we have made are of the reduction of excise tax 
revenues due to the exemptions. 

To identify possible ways to change the RABA adjustment to reduce the
wide shifts caused by the current formula, we relied on discussions we
had with Treasury and DOT officials. We attempted to show how the
options we identified would result in less fluctuation if they had been
applied throughout the TEA-21 time period. We did not attempt to project
how these alternatives would affect future funding levels under 
different highway receipt scenarios. To identify ways to enhance 
Highway Trust Fund revenues we used our past work on heavy truck use. 
In addition, we interviewed government and industry officials from 
such organizations as the American Road and Transportation Builders 
Association. We did not attempt to evaluate the fiscal or public 
policy implications of any of these proposals. 

[End of section] 

Footnotes: 

[1] U.S. General Accounting Office, Highway Funding: Problems with 
Highway Trust Fund Information Can Affect State Highway Funds, 
[hyperlink, http://www.gao.gov/products/GAO/RCED/AIMD-00-148] 
(Washington, D.C.: June 2000); and U.S. General Accounting Office, 
Applying Agreed-Upon Procedures: Highway Trust Fund Excise Taxes, 
[hyperlink, http://www.gao.gov/products/GAO-02-379R] (Washington, 
D.C.: February 2002). Our work was carried out in accordance with 
generally accepted government auditing standards. 

[2] For the purposes of this testimony, we use the term gasohol to 
refer to all types of ethanol blended fuels. While biomass methanol 
fuels are also eligible for partial tax exemptions, Treasury does not 
separately track the small amounts associated with them. 

[3] The General Fund transfer expires at the end of fiscal year 2005. 
To reflect the expiration, Treasury reduces the total federal excise 
tax on gasohol blends by 2.5 cents starting in fiscal year 2006. Under 
Treasury’s approach, the Highway Account is neither benefited nor 
harmed by the expiration. For the purposes of this testimony, we 
estimated the impact of the 2.5 cent General Fund transfer assuming 
the transfer continued through fiscal year 2012. 

[4] Biomass-derived alcohol fuels are chemical compounds made from 
nonfossil material of biological origin and constitute a renewable 
energy source. 

[5] Ethanol blended fuels containing 7.7 percent ethanol and 5.7 
percent ethanol qualify for a 4.058 cents and 2.978 cents per gallon 
exemption, respectively. TEA-21 extended the exemption for gasohol 
fuels through fiscal year 2007 and provided for a phased-in reduction 
in the exemption for gasohol. 

[6] Typically, IRS certifies quarterly excise tax collections 6 months 
after the end of the quarter. This is to allow sufficient time for 
receipt and processing of the tax returns, including returns filed 
late. Even though IRS certifies collections 6 months after the end of
a quarter, certifications for any given quarter routinely contain some 
amounts related to prior quarters. 

[7] Prior to December 2000, the distribution process was linked to 
OTA’s receipt estimates for inclusion in the president’s budget. 

[8] An adjustment of this type is made every year to correct for the 
difference between the actual amounts received in the fourth quarter 
of the previous year and the estimated amounts for that quarter. 

[9] See, for example, [hyperlink, 
http://www.gao.gov/products/GAO/RCED/AIMD-00-148]. 

[10] [hyperlink, http://www.gao.gov/products/GAO-02-379R]. 

[11] FHWA is developing a model to project Highway Trust Fund receipts. 

[12] All estimates of revenue forgone by the Highway Account are 
presented in constant 2001 dollars. 

[13] The General Fund transfer expires at the end of fiscal year 2005. 
To reflect the expiration, Treasury reduces the total federal excise 
tax on gasohol blends by 2.5 cents starting in fiscal year 2006. Under 
Treasury’s approach, the Highway Account is neither benefited nor 
harmed by the expiration. For the purposes of this testimony, we 
estimated the impact of the 2.5 cent General Fund transfer assuming 
the transfer continued through fiscal year 2012. 

[14] U.S. General Accounting Office, Budget Issues: Budgetary 
Implications of Select GAO Work For Fiscal Year 2001, [hyperlink, 
http://www.gao.gov/products/GAO-OCG-00-8] (Washington, D.C.: March 31, 
2000). 

[15] U.S. General Accounting Office, Tax Policy: Effects of the 
Alcohol Fuels Tax Incentives, [hyperlink, 
http://www.gao.gov/products/GAO/GGD-97-41] (Washington, D.C.: March 6, 
1997). 

[End of section]