Source: U.S. Department of Transportation, Bureau of Transportation Statistics (BTS), Office of Airline Information (government). BTS also compiles aviation revenue passenger-miles (RPM) estimates for the most recent month based on revenue passenger-miles data published on air carrier web sites.
Aviation revenue passenger-miles data used in the Transportation Services Index are found in the T-1 dataset complied for the T-100 database by the Bureau of Transportation Statistics' Office of Airline Information (OAI). Airlines submit T-100 data monthly to OAI. The submitted data are then processed and edited by OAI.
The T-100 databases include data reported by U.S. air carriers operating between airports located within the boundaries of the United States and its territories. These data fields contain information on passengers, freight, and/or mail enplaned at the origin airport and deplaned at the destination airport. The data are published monthly in Air Carrier Traffic Statistics (the Green Book).
Data in Air Carrier Traffic Statistics consist of passenger and cargo capacities and traffic actually carried by carrier geographic entity (e.g., domestic, Latin America, Atlantic, and Pacific) and class of service in both scheduled and nonscheduled (or charter) service for the most recent month and 12-month period, and similar data for like periods in the previous year. Data are summarized by carrier entity (D, L, A, and P) and carrier group (major, national, etc.).
Air Carrier Traffic Statistics is based on data reported to the U.S. Department of Transportation (USDOT) by carriers holding a certificate issued under Section 401 of the Federal Aviation Act of 1958 and that operate aircraft designed for a maximum seating capacity of more than 60 seats or a maximum payload capacity of more than 18,000 pounds or that conduct international operations.
Pursuant to 14 CFR Part 217 and Part 241, data are collected by OAI within the Bureau of Transportation Statistics (BTS) on Form 41, Schedule T-100.
The T-100 program was instituted by the USDOT effective January 1, 1990.
Large U.S. certificated air carriers, small certificated air carriers, and commuter air carriers are required to complete Form 41 Financial and Traffic Reporting Requirements. These forms are completed both electronically (mainly by the large carriers) and on paper (small and commuter carriers).
The T-1 dataset includes information on all U.S. commercial air carriers, except air taxis. The dataset does not include foreign air carriers, entities that provide commercial services illegally, in-house air transportation (e.g., corporate jets), general aviation, and air taxis.
Data Quality Questions
For an overview, see also Aviation Revenue Freight Ton-Miles.
- Is this data source a frame or sample?
The data source is a sample.
- Does the sample cover the entire frame? Or is some group missing or underrepresented in the sample?
- The actual data coverage falls short of the theoretical coverage due to carriers failing to report, late reporting, and errors. Reasons for nonreporting include: new carriers that take time to learn the reporting requirements, noncompliance, and lost records. Analysis of the data at the carrier level shows that carriers have gaps in their reporting (or no report) for the months that appear to be missing data. However, gaps are rare for the largest carriers, and these carriers account for most of the air transportation services provided. A more common occurrence is for carriers to report data after the normal reporting period. Similarly, errors may occur in the data even though OAI conducts audits of the carrier submissions. For example, a carrier may misreport the number of passengers on a particular route. Errors that are captured in the audit process are sent back to the carriers for revision and resubmission.
Revenue passenger-miles data collected by BTS from carriers' web sites cover 17 larger carriers and 13 small carriers, and about 97% of the total revenue passenger-miles reported to OAI each month by the reporting carriers.
- Are the data available monthly?
- How soon are the data available after the month is over?
The T-1 data are available to the public about 10 weeks after the month they represent. Aviation revenue passenger-miles data collected from carriers' web sites are available in two weeks after the month they represent.
- Are the data easy to access and use?
The data are easy to access but require some processing to obtain aggregates.
- Are the microdata available for use?
- Are there duplicate records?
- Are there outliers in the data?
- Are data missing for individual records? If so, how are they identified?
Some data are missing for carriers that fail to report. However, consistent reporting by the largest carriers alleviates the problem.
- How accurate are the key data fields?
The problem of inaccurate reporting exists, but is infrequent.
- Are variances available for this data source? If so, what method was used to calculate variances?
No. BTS has no information on the accuracy of revenue passenger-miles data collected from carriers' web sites. However, BTS analysis of carriers' RPM release history showed that revisions to original RPM releases were relatively small.
- Are the data comparable over time within the data source? If not, can data be made to be comparable (i.e., combining two data series)?
The major inconsistency in the data is the expansion to include small certificated and commuter carriers who previously reported data under 14 CFR Part 298c. These data are available on a quarterly basis over the entire period, but only cover scheduled operations.
Other Questions and Important Information
- Is sufficient documentation available for the data source?
- Data dictionary:
Documentation is available in the form of data dictionaries and processing steps but is not available for the audit process conducted by OAI.
- Detailed description of the methodology:
Information is not available to BTS.
- Estimation methods:
Information is not available to BTS.
- Are other sources available for the same data?
The possibility of supplementing the T-1 data with data from the Air Transport Association (ATA) and the Official Airline Guide (OAG) is being examined. These sources provide information on actual RPM (ATA) and schedule information (OAG) that is available sooner than the T-1 data.
Aviation revenue passenger-miles data collected directly from carriers' web sites are used to estimate total RPM for a month when RPM for that month is not available from OAI.
- Who is the contact for the data source?
Bureau of Transportation Statistics, 1-800-853-1351, firstname.lastname@example.org