Series details: CRDA/14

The Heavy Goods Vehicle dataset contains records of the Continuing Survey of Road Goods Transport (CSRGT) from 1 January 1976 to 31 December 2003. The CSRGT sampled vehicles on Operators' Licences registered with the Department and collated data about one week's activity from each vehicle in the sample. The sample was spread evenly over the year so that the sample was 'self weighting' in respect of seasonal effects, holidays etc.

The key reason behind the collation of statistics relating to heavy goods vehicles was to provide essential information for transport policy purposes. Transport trends in road freight haulage vis-a-vis other types of internal haulage is considered vital information for an integrated transport policy. The statistics of the Continuing Survey of Road Goods Transport [GB] have also been utilised as follows:

• For specific studies relating to transport matters such as 'Adjustment to National Taxation Systems' (ANTS); and environmental and other costs of lorries.
• Ad hoc queries on transport matters for specific purposes.
• Providing some of the statistics required by the EEC.1

Within the Department for Transport, maintenance of the dataset and compilation of statistics using its findings is the responsibility of the Transport Statistics 4 unit of the Transport Statistics Freight division, Freight Distribution and Logistics section. The section is responsible for co-ordination of policy development across all freight transport modes within the wider industrial context of supply chain management developments. See the Administrative History of the Transport Departments for further information.

This dataset series contains records of the Continuing Survey of Road Goods Transport (CSRGT) from 1 January 1976 to 31 December 2003. The CSRGT samples vehicles on Operators' Licences registered with the Department. The data is concerned with heavy goods vehicles (over 3.5 tonnes gross vehicle weight in 1997) using public roads and includes information on journeys made, weight of vehicle, types of goods moved and fuel used, together with some related documentation. It covers heavy goods vehicles registered in the United Kingdom (including Northern Ireland from 1998) only; survey data relating to international road haulage and small goods freight are compiled separately. Only travel on public roads is surveyed; work done on private land e.g. sites is not included.

In March 2005 the UK Government launched a new Sustainable Development Strategy which outlines a plan of sustainable development though to 2020. Within this strategy, there are a number of identifiable indicators that are transport-related, namely road freight indicators such as Heavy Goods Vehicles (HGV) CO2 emissions, kilometres, tonnes and Gross Domestic product.2Although road freight has shown a strong increase, road freight intensity as measured by Heavy Goods Vehicle (HGV) kilometres per GDP has tended to decline since the mid-1960s, (ie freight transport has grown more slowly than GDP). This is thought to be due to a shift towards the use of larger articulated vehicles carrying a greater payload.3

From 2004, the Department for Transport elected to analyse all of its data by means of a Microsoft Access database; although the original system was still held in SQL-Server format. It was agreed that only the Access database would be selected for permanent preservation for datasets created 2004 onwards (ie from CRDA/14/DS/29). Note that the 'Respondent Names' and 'Population' tables (ie respondents names and addresses and another containing HGV population data) were also omitted from the survey data transferred in 2004 and thereafter.4

Further transfers of the Survey of Heavy Goods Vehicles Dataset to NDAD are expected.

The Survey of Heavy Goods Vehicles Dataset and its related documentation are public records under the Public Records Acts 1958 and 1967. The National Archives has assigned the dataset and its related documentation the class reference LM 1.

Access to the Survey of Heavy Goods Vehicles Dataset and its related system documentation is closed for 30 years, with the exception of data and documentation dated 1976 - 1977. The data is statute barred under the Statistics of Trade Act 1947. While most systems documentation is restricted for 30 years, much other related documentation is open for public access via the Dataset Documentation Catalogue (e.g., Reviews of Statistical Road Freight Surveys and Reports of the Continuing Survey of Road Goods Transport).

The Survey of Heavy Goods Vehicles Dataset is subject to Crown Copyright. Copies may be made for private study and research purposes only.

The Survey of Heavy Goods Vehicles Dataset is subject to registration under the Data Protection Act. Subject access to the data as defined by the Act is permitted; prior authorisation must be obtained from the Department for Transport.

The language of the materials is English.

Documents relating to the Heavy Goods Vehicles Dataset have been transferred to NDAD from the Department for Transport and its predecessors. See the Dataset Documentation Catalogue for further details of these items.

The Department publishes the dataset's findings annually in reports produced since 1976. In June 2006, the first edition of Road Freight Statistics was produced with the aim of incorporating, in one annual publication, the main series on the activities of UK-registered heavy goods vehicles, both domestically and internationally, non-UK registered heavy goods vehicles in Great Britain, and GB-registered vans. It therefore supersedes the previous publications such as its Transport Statistics Report: Transport of Goods by Road in Great Britain. Up to and including 1979 the reports included figures for all registered goods vehicles, including figures from the Small Goods Survey, the last of which was carried out in 1976. From 1980, only the results of the CSRGT were included. Many of the reports present a detailed analysis of the survey in the form of a commentary on recent trends and a set of reference tables. Up until the report generated for 2005, all statistics had related to Great Britain only.

Copies of statistical returns and of five yearly returns (not published since 1997) have been transferred to NDAD. See the Dataset Documentation Catalogue for further details.

Further explanatory notes and details concerning codings and classifications relating to the datasets are also located within the Reports of the Continuing Survey of Road Goods Transport 1977-2003 (CRDA/14/DD/2), as held in the Dataset Documentation Catalogue.

Not known.

The application was most recently run on IBM or compatible PC with MS-DOS.

Prior to 1984, the data was maintained in a purpose-built system held at the Department for Transport in Hastings. In 1984, the data was transferred to a SIR (Statistics and Analysis, Integrated Applications, Relational Database) relational database management system manufactured by SIR Pty Ltd of Milsons Point, New South Wales, Australia. The SIR package continued in use until 2004 when the data was thereafter analysed using a Microsoft Access (2000) database.

The data was transferred from a purpose-built system at the Department for Transport at Hastings, to a SIR database, in 1984. The data was copied from old computer files and up until 1982, only two records were available: information (VEHICLE), and journey information (JOURNEY). From 1982, the data was held in 4 records: vehicle information (VEHICLE), journey information (JOURNEY), journeys comprising 1 to 4 stops (MULTISTP), and journeys comprising more than 4 stops (MULTITRP). The JOURNEY records were not input from the survey questionnaire but were derived from the MULTISTP and MULTITRP records.

In 2003, major changes in the CSRGT survey sample methodology took place following a quality review of the Department for Transport's (DfT) road freight surveys. In accordance with these changes, the DfT decided to procure a replacement database system to support the CSRGT (GB) Survey Process. Note that this new CSRGT (GB) system (as of 2004 ie CRDA/14/DS/29) was originally held in SQL-Server format but the Department sought to analyse all of its data by means of a MS Access database. As complete details for the CSRGT (GB) system structure are unavailable, it is only presumed that the SQL-Server and the Access database were intrinsically linked in relationship to one another. Only the MS Access component of the system has been selected for permanent preservation. While retaining most of the core data captured in previous years, the new system no longer arranged the survey data as four key records. For further details, see the Links to dataset catalogues, reference CRDA/14/DS/29.

All records, in each year of the dataset, include the key field REGKEY (registration mark and survey year). This key remains confidential.

The data is closed.

The Department holds lists of heavy goods vehicles on Operators Licence; the lists are regularly updated.

The data is based on a sample of about 350 vehicles each week. [Note that due to changes in the survey methodology during 2003, fewer questionnaires were posted in 2004 than in 2003, an average of 330 per week].5The operator of the vehicle provides details of all trips undertaken in one week; including domestic and foreign trips. Data includes type of activity, weight of vehicle, public and own account operation, length of haul, commodities carried, mode of appearance of load and inter-regional flows. From 1989 fuel consumption is included.

The data was collated using a questionnaire, a copy of which can be viewed by consulting, for example, document reference CRDA/14/DD/2/28 within the Reports of the Continuing Survey of Road Goods Transport 1977-2005 (CRDA/14/DD/2), as held in the Dataset Documentation Catalogue.

There is some inconsistency in the format of vehicle registration mark data (REGKEY): some marks have preceding spaces, and others have one or more embedded spaces separating the mark components. For this reason, searches based on the REGKEY field may give incorrect results if exact matches are specified.

For datasets dated 2004 onwards (ie from CRDA/14/DS/29), it is recommended that any comparative analysis of data with previous years be undertaken with caution due to the major survey methodological changes which took effect following a quality review of the Department's road freight surveys in 2003.

Further information concerning the survey sample design and any sampling errors are available within the appendices of the Reports of the Continuing Survey of Road Goods Transport 1977-2005 (CRDA/14/DD/2). See the Dataset Documentation Catalogue to view these reports.

Details of the content and transformation validation checks performed by NDAD staff on the Survey of Heavy Goods Dataset are contained in the dataset catalogues, see Links to dataset catalogues.

Dataset catalogues provide more detailed information about individual datasets, and are currently available for the following dataset(s):

1. Dataset Documentation Catalogue, reference CRDA/14/DD/1/1, p.3

2. Dataset Documentation Catalogue, reference CRDA/14/DD/12/1, p.120

3. UK Sustainable Development website [Department for Environment, Food and Rural Affairs (Defra), Sustainable Development Unit] specifically: http://www.sustainable-development.gov.uk/sustainable/quality04/maind/04d21.htm, page on "Indicators of Sustainable Development" consulted on 3 May 2006.

4. Note of communication between NDAD and the Department for Transport on 6 March 2006.

5. Dataset Documentation Catalogue, reference CRDA/14/DD/2/29, p.50.