Data Limitations and Coverage

Data Limitations

The list below contains the major limitations of the database that users should take into consideration:

• Federal government data are compiled for the federal fiscal year, which begins on October 1, while state and local data are for fiscal years that generally start in July, except for four states with other starting dates (Alabama and Michigan in October, New York in April, and Texas in September). While this may create a small error in totals for any given year, the data are suitable for illustrating trends in public transportation finance.
• State and local governments data for census years are full counts and are not subject to sampling errors, whereas the data for noncensus years are estimated from annual surveys of the Bureau of the Census, which are subject to sampling variability of less than 3 percent.
• The database is limited to civilian transportation, including civilian activities of the U.S. Army Corps of Engineers (USACE); such as construction and maintenance of channels, harbors, locks, and dams; and civilian transportation-related activities of the U.S. Coast Guard (USCG).
• State and local transportation-related property taxes are not covered due to lack of data. For example, personal property taxes on motor vehicles and taxes on motor carriers based on assessed value of property are not included in the state and local highway revenues.
• Not all transportation-related activities by government agencies outside of the U.S. Department of Transportation are covered due to lack of data. For example, expenditures of the Environmental Protection Agency (EPA) for transportation-related pollution programs are not covered because this portion of the spending is not separately reported in the budget.

Revenues and Expenditures - Definition

Revenues: Transportation revenues include money received by the government from transportation-related taxes, user charges, or fees earmarked to fund transportation-related expenditures. The following types of receipts are not accounted for as transportation revenues:

• Taxes collected from users of the transportation system that go to the general fund,¹
• Nontransportation-related general fund revenues, which are used to finance transportation activities,
• Proceeds from borrowing, whether short-term or long-term,
• Proceeds from sale of investments and the payment of loans,
• Transfers from agencies or funds of the same government.

Expenditures: Transportation expenditures consist of money paid out for transportation-related activities by the government.² In this definition, expenditures include payments from all sources of funds, including transportation trust funds, general funds, and proceeds from borrowing. The following types of outlays are not considered as transportation expenditures:

• Loans or other extensions of credit.
• Purchase of securities for investment purposes (recorded loss on the sale of investments is, however, treated as expenditure).
• Payments for retirement of debt principal (long-term or short-term), which are reported with debt statistics. Interest on debt is, however, reported as expenditure.³
• Transfer to other agencies or funds of the same government.

Data Coverage

Highways

Revenues.⁴ Federal highway revenues constitute the portion of money paid into the Highway Account of the Highway Trust Fund (HTF). The HTF revenues are derived from excise taxes on motor fuel, motor vehicles, tires, parts and accessories for trucks and buses, and interest income earned on balances of the Trust Fund. ⁵ Motor fuel taxes, which are included in the HTF, are taxes levied only on motor fuels used by highway users.

State and local highway revenues are raised through taxes on motor fuels, motor vehicle licenses, and motor vehicle operator licenses, along with charges on regular and toll highways, and parking facilities. For state and local governments, motor fuel taxes include taxes on gasoline, diesel oil, aviation fuel, "gasohol," and any other fuels used in motor vehicles or aircraft. Motor vehicle operator license taxes cover licenses for the privilege of driving commercial and private motor vehicles. Motor vehicles license taxes are taxes imposed on owners or operators of motor vehicles for the right to use public highways, such as fees for title registration, license plates, vehicle inspection, vehicle mileage and weight taxes on motor carriers, highway use taxes, and off-highway fees.⁶ Parking facility charges are imposed on on-street and off-street parking meters and charges and rentals from locally owned parking lots or public garages. Regular highway charges include reimbursements for street construction and repairs, fees for curb cuts and special traffic signs, and maintenance assessments for street lighting, snow removal, and other highway or street services unrelated to toll facilities. Toll highway charges include fees from turnpikes, toll roads, bridges, ferries, and tunnels; rents and other revenue from concessions (service stations, restaurants, etc.); and other charges for use of toll facilities.

Expenditures. Highway expenditures consist of outlays of the Federal Highway Administration and the National Highway Traffic Safety Administration and outlays for road construction activities managed by the Department of the Interiors National Park Service, the Bureau of Indian Affairs, the Bureau of Reclamation, the Bureau of Land Management, the Department of Agricultures Forest Service, the Department of Housing and Urban Development, and other federal agencies. The Federal Highway Administration expenditures include outlays for federal-aid-highway programs (financed from the HTF) and the Interstate Substitution and Railroad Crossing Demonstration program (financed from the general fund). The federal-aid highway program fund is apportioned to states using formulas for planning, constructing, and improving the nations highway system. Outlays of the National Highway Traffic Safety Administration (NHTSA) are used for setting and enforcing safety performance standards for motor vehicles and motor vehicle equipment, investigating safety defects in motor vehicles, setting and enforcing fuel economy standards, helping states and local communities reduce the threat of drunk drivers, and promoting the use of safety belts and child safety seats. NHTSAs outlays in the form of grants to state and local governments for conducting local highway safety programs are also included.

For state and local expenditures, outlays of the following activities are included:

1. Maintenance, operation, repair, and construction of regular highways, streets, roads, alleys, sidewalks, bridges, tunnels, ferry boats, viaducts, and related structures.


Examples: Snow and ice removal and application of salt and sand (including that by sanitation or street cleaning agencies, if identifiable); street or highway lighting and related fixtures; traffic signals; highway and traffic design, planning, and engineering if handled by public works or highways agency; highway safety; and construction and maintenance of such highway-related items as curbs, gutters, crosswalks, grade separations, trestles, railroad crossings, and storm drains integral to highway projects.


2. Maintenance, operation, repairs, and construction of highways, roads, bridges, ferries, and tunnels operated on a fee or toll basis.

Examples: Turnpikes, toll roads, toll bridges, toll ferries (including docks and related terminals), toll tunnels, and all related activities and facilities such as snow and ice removal, highway police and fire protection units if administered by the toll authority, lighting and light fixtures, design and engineering, garages and administrative buildings of toll authorities, operation of toll booths, drawspans, rest stops, and service areas by the toll authority itself.


3. Provision, construction, maintenance, and operation of local government public parking facilities operated on a commercial basis.

The source data do not cover the following activities in the state and local expenditures for highways:

1. Patrol or policing of streets and highways and traffic control activities of police or public safety agencies.
   
   
2. Enforcement of parking regulations and laws such as meter readers, parking facilities for exclusive use (e.g., by meter readers) of government employees, and parking areas connected to a specific type of facility, such as those for a public sports stadium.
   
   
3. Debt service on toll facility debt.

Note that state and local governments highway expenditures reported by the Census Bureau are slightly lower than those reported in the FHWAs Highway Statistics because data from the FHWA include outlays for highway activities such as law enforcement and patrols and policing of streets and highways not included in the Census data. Although the FHWA data provide better coverage of state and local highway expenditures, in order to maintain consistency among the different modes regarding the types of expenditures included in the state and local data, these data were not used. Table 2 outlines the major differences in Census Bureau and FHWA calculation of state and local highway transportation financial statistics.

Table 2. Comparison of the U.S. Census Bureau and Federal Highway Administration Calculations of State and Local Transportation Financial Statistics

Transit

Revenues. Federal transit revenues include the money paid into the Mass Transit Account of the HTF. The Highway Revenue Act of 1982 established the Mass Transit Account within the HTF and provided that a certain proportion of federal fuel taxes be assigned to it. Although highway users pay the taxes, these funds are treated as federal transit revenues in this report.

State and local transit revenues comprise money generated from operations of the public mass transportation system (i.e., rapid transit, subway, bus, street railway, and commuter rail services), such as fares, charter fees, advertising income, and other operations revenues.

Expenditures. Federal transit expenditures include grants to state and local agencies for the construction, acquisition, and improvement of the mass transportation facilities and equipment and for payment of operating expenses. Also included are Federal Railroad Administration (FRA) commuter rail subsidies related to the transition of Conrail to the private sector,⁷ research and administrative expenses of the Federal Transit Administration (FTA), and federal interest payment contribution to Washington Metro Area Transportation Authority (WMATA) loans.

State and local transit expenditures include all amounts of money paid out for operation, maintenance, and construction of the public mass transit systems, including subways, surface rails, and buses. For example, expenditures on rapid transit; subways, surface rail, and street railroad systems; commuter rail lines; trolleys and light rail; related stations, tracks, depots, and rail yards; acquisition of right-of-ways; transit police employed directly by utility; subsidies to public mass transit systems (but not private ones); and buses are included in transit spending. Payments in support of privately owned and operated transit utility operations, including railroads, are also included in the state and local transit expenditures. These are payments or subsidies to private bus companies, railways, light rail, or other private passenger transportation systems for construction, purchase of equipment, and operations and subsidies to railroads for continued service to rural or outlying areas.

The following transit activities are not covered in the state and local spending for transit: systems solely to transport students; systems exclusively for handicapped or senior citizens; systems owned but operated under private contract without financial oversight; depreciation of assets; activities not directly related to utility operation, such as administration of utility debt and payments-in-lieu-of-taxes; and benefits paid to utility employees by employee retirement systems. Also excluded are payments to private firms to provide transportation for government employees, such as shuttle bus service between public buildings, and payments to private firms for transporting students.

Rail

Revenues. Railroad activity generates revenues in the form of fuels and property taxes, but these are not treated as transportation-related revenues in the report.⁸ Fuel taxes collected from railroads are channeled into the general fund for deficit reduction and hence do not fall under the definition of transportation-related revenues. State and local governments collect property taxes from the rail mode, and some of these proceeds may be used to finance transportation activities. That portion of the state and local governments property tax revenue, which is used for transportation, is not accounted for in this report because of lack of data. For a similar reason, transportation-related property taxes for other modes are also not covered. Amtrak, the passenger railroad service, generates revenues from passenger fares, but since Amtrak is not an entity of the federal government its revenues are not treated as transportation-related revenues.

Expenditures. Federal rail expenditures include expenses of the Federal Railroad Administration (FRA) for its programs, namely, capital grants to Amtrak, settlement of railroad litigation, northeast corridor improvement, local rail freight assistance, mandatory passenger rail service payments, safety and operations, railroad research and development, Conrail labor protection (which provided benefits to Conrail employees deprived of employment because of workforce reduction and other actions), railroad rehabilitation and improvement, the Alaska railroad revolving fund, regional rail reorganization program, Amtrak corridor improvement, freight line rehabilitation, the Penn station redevelopment program, MAGLEV prototype development, next generation high-speed rail, Alameda corridor direct loan financing program, Rhode Island rail development, Alaska railroad rehabilitation, high-speed rail train sets and facilities, emergency railroad rehabilitation and repair, West Virginia rail development, and the Amtrak reform council. Also included are outlays for the rail service program of the former Interstate Commerce Commission and outlays of the former U.S. Railway Association.

The local rail freight assistance program, a program of FRA grants to state governments, has had a 70:30 percent federal to state funding share, respectively, since FY 1982. Due to lack of readily available data, state and local government rail expenditures are estimated based on this ratio.

Air

Revenues. Federal air revenues include passenger ticket taxes and other excise taxes and fees paid by air carriers and passengers. Examples of these are aviation excise taxes, freight waybill taxes, general aviation fuel/gas taxes, ad valorem tax on domestic passenger tickets, international departure and arrival taxes, etc. These revenues are accumulated in the Airport and Airways Trust Fund (AATF). While held by the Treasury, the Trust Fund balance is invested in Government securities, and any interest income earned is deposited back into the Trust Fund.

State and local revenues for air mode are derived from airport charges. These include hangar rentals, landing fees, terminal and concession rents, parking fees at airport lots, and other charges for use of airport facilities or for services associated with their use. In 1992, local governments began collecting passenger facility charges and spending these revenues to finance capital programs. The collection of passenger facility charges was authorized by the Aviation Safety and Capacity Expansion Act of 1990.

Expenditures. Federal air expenditures consist of outlays of the Federal Aviation Administration (FAA) and outlays of the Office of the Secretary of Transportation for air carriers, essential air service, and Commission on Aircraft Security programs. The FAA expenses cover the costs of constructing, operating, and maintaining the national air traffic system, grants for airports, administration of the airport grant program, safety regulation, research and development, etc. In addition, expenses of the Civil Aeronautics Board for the years prior to its abolition and transportation-related expenses of the National Aeronautics and Space Administration (NASA) are included. Transportation-related NASA expenditures include outlays for research and development, construction of facilities, and research and program management.

State and local expenditures for air constitute outlays for the operation and maintenance of airport facilities, as administered by local airport and port authorities with responsibilities for promoting safe navigation and operations for air modes, and regulation of the airline industry. Examples of these expenditures are outlays on publicly operated airfields and related facilities (runways, terminals, control towers, maintenance facilities, and the like); intergovernmental payments for construction, operation, or support of publicly owned airports; support of private airports; and airport police if either an integral part of the airport authority or a payment to regular police agency. Purchase and operation of government-owned aircraft, such as police helicopters and state civil air patrols, are not covered in the state and local government air transportation expenditures.

Water

Revenues. Federal water revenues are derived from user charges and taxes paid into the Inland Waterways Trust Fund, the Harbor Maintenance Trust Fund, and the Oil Spill Liability Trust Fund. Interest incomes from these trust fund balances are also included. Moreover, tolls and other charges collected by the Panama Canal Commission,⁹ receipts of the boat safety account of the Aquatic Resources Trust Fund, and receipts of the Offshore Oil Pollution Trust Fund and Deepwater Port Liability Fund are accounted for in the federal water and marine revenues.¹⁰

State and local revenues are generated through state and local water charges. These include canal tolls (including Panama Canal), rents from leases, concession rents, and other charges for use of commercial or industrial water transport and port terminal facilities and related services. Fees and rents related to water facilities provided for recreational purposes, such as marinas, public docks, etc., and toll ferries are excluded.

Expenditures. Federal expenditures comprise outlays of the U.S. Coast Guard for transportation-related programs and activities, such as marine safety, environmental compliance and restoration, alteration of bridges, oil spill recovery, aids to navigation, marine environmental protection, search and rescue, and ice operations. All expenses of the U.S. Maritime Administration are included, such as subsidies for construction and operation of vessels by U.S.-flag operators, research and development, training of ship officers, federal ship financing fund, ready reserve force, ocean freight differential, maritime security program, maritime guaranteed loan, etc.¹¹ Also included are those expenses of the U.S. Army Corps of Engineers for construction, operation, and maintenance of channels, harbors, locks, and dams, and protection of navigation. Moreover, salaries and other expenses of the Federal Maritime Commission, expenses of the Panama Canal Commission for the years until the hand over of Panama Canal to Republic of Panama in December 1999,¹² and operations and maintenance expenses of the Saint Lawrence Seaway Development Corporation are accounted for.

Water and marine expenditures at the state and local level constitute payments for the provision, construction, operation, maintenance, and support of public waterways and harbors, docks, wharves, and related marine terminal facilities and the regulation of the water transportation industry. These include commercial port facilities, canals, harbors, and other public waterways; dredging of same; public docks, piers, wharves, warehouses, cranes, and associated terminal facilities; and regulation and inspection of the commercial water transportation industry. Expenditures on recreational docks and marine facilities, such as public marinas devoted to pleasure boaters, are excluded.

Pipeline

Revenues. Federal pipeline revenues are raised through pipeline safety user fees assessed on a per-mile basis. The assessments are made on each pipeline operator regulated by the Office of Pipeline Safety (OPS) in the DOTs Research and Special Programs Administration (RSPA). The OPS began charging companies a fee for using gas transmission pipelines in 1986. Between 1986 and 1994, the fee almost doubled from $23.99 per mile of pipeline to $44.94 per mile. In 1995, the fee doubled once more to $95.57. There are no state and local revenues for pipeline.

Expenditures. Pipeline expenditures comprise outlays for the Research and Special Programs Administrations (RSPA) grants-in-aid activity for state pipeline safety programs, enforcement programs, and research and development. Federal government outlays for pipeline programs started in FY 1988. State and local government spending for pipeline is obtained from the Office of Pipeline Safety under RSPA.

General Support

Revenues. General Support revenues come from fees paid by registered shippers of hazardous materials, which are held in the Emergency Preparedness Fund. The Research and Special Programs Administration (RSPA) administers and apportions the revenues to states and territories through the Hazardous Materials Emergency Preparedness (HMEP) grant program.

Expenditures. Expenditures of the following agencies and offices have been included under the General Support category (although their funding may come from different sources): The Office of Inspector General, the Bureau of Transportation Statistics, the National Transportation Safety Board, the former Interstate Commerce Commission until its termination in December 1995, the Surface Transportation Board, all expenses of the RSPA (except pipeline expenditures) and the Office of the Secretary of Transportation (except for payments to Air Carriers and Commission on Aircraft Safety).

Capital Expenditures

A capital expenditure is any expenditure that adds to the productive capacity of the economy. Specifically, a capital expenditure in transportation is any expenditure that increases the capacity and efficiency of the transportation infrastructure, whether by reducing travel times, improving access, creating capacity for more passenger and goods traffic, reducing costs, or reducing adverse safety and environmental impacts. It includes outlays for construction of transportation infrastructure, purchase of land and existing structures, purchase of equipment, research activities, and outlays for major maintenance and repairs to existing infrastructure and equipment.

Federal Capital Expenditures

At the federal level, capital expenditures include outlays for the construction of highways and bridges, airports and rail systems, waterway systems, acquisition of land for these purposes, acquisition of equipment such as air traffic control infrastructure, and outlays for research. Outlays for significant repairs and maintenance such as the U.S. Army Corps of Engineers Rehabilitation of Channels and Harbors program are included, since they represent increases in the capacity of the infrastructure, but routine maintenance expenditures are not included. Specific federal government programs or activities, which are included in the capital expenditures in this report, are listed below by mode.

Highways

Highway capital expenditures are obtained directly from the Highway Statistics reports of the Federal Highway Administration. Highway capital expenditures constitute those outlays associated with highway improvements, including land acquisition and other right-of-way costs; preliminary and construction engineering; construction and reconstruction; resurfacing, rehabilitation, and restoration costs of roadway and structure; system preservation activities; and installation of traffic service facilities such as guard rails, fencing, signs, and signals (FHWA, 2000). Research expenditures for the highway mode, which could not be determined as they are not distinguished from operational expenditures data published by FHWA in Highway Statistics, are not included. Maintenance costs required to keep highways in usable condition are also not included because these outlays do not extend the service life of a highway beyond the original design.

Transit

For transit, one half of the FTAs research expenditures are considered as capital. This assumption was made in consultation with the FTA.

Rail

The funding for the following FRA programs is included under rail capital expenditures: Railroad R&D; the Local Rail Freight Assistance program, which provides matching grants to states for rail freight planning and acquisition, rail facility construction, and track rehabilitation with respect to law volume freight lines (generally owned and operated by small and regional rail roads); the Amtrak Corridor Improvement Loan, which was included in the DOT FY 1990, 1991 and 1992 Appropriations Act and was specifically available for rehabilitation of a section of the Amtrak route between Chicago and St. Louis owned by Southern Pacific Chicago-Saint Louis (SPCSL) Corporation; Freight Line Rehabilitation; the Northeast Corridor Improvement program; and a part of Amtrak Grants, which were obtained directly from FRA.

Air

Federal capital expenditures for air include FAAs outlays for facilities and equipment program; research, engineering and development program; facilities, engineering, and development program (prior to FY 1988); and for Washington D.C. metro area airports construction. In addition, all NASA aeronautics-related expenditures are included.

Water

For water, funding for the following programs is included under capital expenditures: U.S. Coast Guard capital expenditures, which covers Acquisition, Construction and Improvement program; Alteration of Bridges program; MARAD capital expenditures, which includes Ship Construction and Federal Ship Financing programs; U.S. Army Corps of Engineers capital expenditures (Construction of Locks and Dams program, Construction of Channels and Harbors program, Rehabilitation of Locks and dams program, Rehabilitation of Channels and Harbors program, and 25 percent of the Mississippi River and Tributaries (MR&T) program expenditures (This conforms to the rule of thumb used by the Corps of Engineers to allocate the MR&T program expenditures between transportation and flood control)); and Saint Lawrence Seaway Development Corporation and Panama Canal Commission capital expenditures, which were obtained directly from these agencies.

Pipeline

For the pipeline mode, all of the Pipeline Safety Research and Development program expenditures are accounted for as capital.

State and Local Capital Expenditures

State and local capital expenditures, which are obtained from the Census Bureau, consist of outlays for construction, purchase of land and existing structures, and purchase of equipment.¹³

Construction covers outlays for production, additions, replacements, or major structural alterations to fixed works, undertaken either on a contractual basis by private contractors or through a government's own staff (i.e., force account). It includes initial production of buildings and structures, initial permanent improvements (other than buildings) that add value to land, and subsequent improvements representing major permanent structural alterations that materially extend the useful life of fixed works. It covers all costs of materials, supplies, and labor that are reasonable and necessary to place an asset in its intended location and prepare it for its intended use, namely, professional fees for architects, engineers, appraisers, and attorneys associated with feasibility studies; preliminary engineering, planning, and design; or related developmental costs such as overhead, office costs, and other purchased construction-related services. It also includes centralized architecture, design, and planning offices whose main role is to support public construction projects, including related salaries and wages, insurance, professional services, etc.

Purchase of land and existing structures includes outright purchase, payments on capital lease-purchase agreements or installment purchase contracts, costs associated with eminent domain (including purchase of rights-of-way), and tax or special assessment foreclosure. It covers all ancillary costs associated with the transaction, such as legal and title fees, surveying fees, appraisal and negotiation fees, damage claims. It does not cover construction-related site preparation costs, including clearing, filling, leveling, and razing unwanted structures.

Purchase of equipment consists of not only purchase and installation of apparatus, furnishings, motor vehicles, office equipment, etc. (including both additional equipment and replacements purchased outright or through capital lease or installment purchase contracts) but also other related expenditures such as transportation and installation charges, which are necessary to place the equipment for its intended use.

Maintenance and repair expenses for the purpose of keeping property in an ordinarily efficient operating condition and which are not considered permanent structural alterations that materially extend the life of the asset are not accounted for under capital expenditures.

Federal Budget Authority and Obligations

Budget authority is the authority provided under law to enter into obligations, which in turn are agreements that will result in immediate or future outlays of government funds. Obligations show government commitment to future transportation outlays but do not indicate when the funds will actually be disbursed or the amounts obligated will be spent. Budget authority is recorded in the year that it first becomes available. Not all budget authority enacted for a fiscal year results in obligations and outlays in the same year; hence they can be available for more than one fiscal year. In this case, the unobliged balance available at the end of a fiscal year will be carried forward for obligation in the following fiscal year.

Highways

Budget authority and obligations for highways are collected from the Budget of the U.S. Government because the FHWAs Highway Statistics report does not provide this data. As indicated in Data Sources, the source of data for highway expenditures is the Highway Statistics report. Budget authority and obligations for highways do not include highway programs by federal agencies outside of the Department of Transportation due to lack of data. Therefore, readers should take into account these differences in coverage and data sources when comparing highway expenditures vis-à-vis budget authority or obligations.

Transit

Budget authority and obligation of the following programs are included for transit: all of the Federal Transit Administration programs, commuter rail subsidies of the Federal Railroad Administration, and the federal government interest payment contributions to the Washington Metro Area Transit Authority.

Rail

For railroad, budget authority and obligations for all programs of the Federal Railroad Administration and administrative expenses and regional rail reorganization program of the former U.S. Railway Association are included.

Air

Budget authority for air includes all of the FAA programs, NASA, and air transportation-related programs of the Office of the Secretary of Transportation. Obligations of all these programs are also accounted for except NASA, due to lack of data.

Water

The following programs are included in water mode budget authority and obligations: all programs of the Maritime Administration, Saint Lawrence Seaway Development Corp., Panama Canal Commission, and Federal Maritime Commission and transportation-related budget authority and obligations of the U.S. Coast Guard. The U.S. Army Corps of Engineers is not included because of lack of data.

Pipeline

Budget authority and obligations for pipeline constitute the Research and Special Programs Administrations pipeline safety program, which includes enforcement, research and development, and grants for state pipeline safety programs.

General Support

Budget authority and obligations of the following agencies and offices are covered under General Support: All programs of the office of the Secretary (except payment to air carriers, essential air service, and commission on aircraft security), all programs of the Office of the Inspector General, all programs of the Research and Special Programs Administration (except pipeline safety fund), salaries and expenses of the Interstate Commerce Commission until its termination, Bureau of Transportation Statistics, and all programs of the National Transportation Safety Board.

Footnotes

¹ This includes revenues assigned to fund nontransportation activities. Examples of such revenues are the portion of the Highway Trust Fund (HTF) allocated to the general fund for deficit reduction, and rail fuel tax revenues also dedicated for deficit reduction.

² In some accounts in the Budget of the U.S. Government, certain offsetting collections or fees and assessments from the public are deducted from disbursements to determine expenditures for the federal government. These collections are those mandated, by statute, to be applied directly to finance agency expenditures rather than being transferred to the Treasury. Most revolving funds operate with such authority. For example, the Aviation Insurance Revolving Fund provides direct support for the aviation insurance program authorized under Chapter 443 of title 49, U.S. Code (formerly title XIII of the Federal Aviation Act of 1958). Income to the fund is derived from the premium deposits for premium insurance coverage issued, income from authorized investments, and binder fees for nonpremium coverage issued. For the federal government, outlays for interest on the public issues of Treasury debt securities are reported as the interest accrues, not when the cash is paid.

³ For state and local governments, interest on debt is reported on actual disbursement.

⁴ Readers should note that federal motor fuel tax revenues include the portion of revenues attributed to highway use only, while state and local motor fuel tax revenues constitute taxes on any fuels used in motor vehicles or aircraft.

⁵ Effective 10/01/98, the Highway Trust Fund ceased earning interest on its invested balances, per Section 9004(a) of TEA-21.

⁶ These do not include personal property taxes on motor vehicles; sales or gross receipts taxes on the sale of motor vehicles; taxes on motor carriers based on assessed value of property, gross receipts, and net income; and other taxes on the business of motor transport.

⁷ Conrail was privatized in 1987.

⁸ During 1991-95, railroads paid fees to the FRA to cover costs associated with the FRA's rail safety program. The government terminated these collections in 1995.

⁹ Ownership of the Panama Canal Commission was transferred to the Republic of Panama in December 1999.

¹⁰ The Oil Pollution Act of 1990, Public Law 101-380, consolidated balances from the Offshore Oil Pollution Compensation Fund, Deepwater Port Liability Fund and the Clean Water Act Section 311(K) Pollution Fund into the Oil Spill Liability Trust Fund.

¹¹ Public Law 99-198 amended section 901 of the Merchant Marine Act to increase from 50 to 75 percent the amount of agricultural commodities under specified programs that must be carried on U.S.-flag vessels. The increased cost associated with this expanded U.S.-flag shipping requirement stems from higher rates charged by U.S.-flag carriers compared with foreign-flag carriers. The Maritime Administration is required to reimburse the Department of Agriculture for ocean freight differential costs for the added tonnage above 50 percent.

¹² Because ownership of the Panama Canal was transferred in December 1999, expenditures of the Commission for FY 2000 consist of outlays for the first quarter operations. FY 2001 expenses are for the settlement of remaining accident and contract claims against the Commission.

¹³ For detailed discussion refer to U.S. Department of Commerce, Bureau of the Census, Government Finance and Employment Classification Manual, Washington, D.C., available at http://www.census.gov, as of October 2001.