February 1, 2023 - Note:
The transport index will be discontinued after February 1, 2023.
The reason for the discontinuation is the low added value of the transport index for business cycle analysis. The truck-toll-mileage index,which accounts for about 75% of the transport index, already appears no later than the 9th day after the end of the reporting month. By design, the transport index follows a very similar pattern, but is not published until one month after the end of the reporting month.
As at February 1, 2023 - The corona pandemic has clearly shown that politicians and society are strongly interested in economic indicators for which data are available rapidly. In this context, the Federal Statistical Office has created a transport index for its experimental statistics (EXSTAT) category as a new and rapidly available short-term indicator. The transport index is based on the assumption that economic activity requires and generates transport services. The fact that there is such a connection between transport and economic activity has been demonstrated, among others, by the truck toll mileage index. It was developed by the Federal Logistics and Mobility Office (BALM) in cooperation with the Federal Statistical Office and has been published regularly. The index shows a high correlation between truck traffic on German motorways which is subject to toll charges and the monthly production index of manufacturing (see the paper on "Digital process data from truck toll collection as new building block of official short-term statistics" in the 6/2018 issue of the WISTA scientific journal of the Federal Statistical Office).
The transport index project aims to supplement the truck toll mileage index by the other modes of goods transport (air and rail, inland waterways and maritime transport) and provide an additional, even more comprehensive early indicator of short-term economic development. To reach that goal, monthly transport index figures which reflect goods transport by all modes of transport have to be available very rapidly, and the correlation between transport and industrial production in Germany should be higher than with the truck toll mileage index.
The freight transport statistics of the Federal Statistical Office and the statistics of freight transport by road of the Federal Motor Transport Authority, which record freight transport by mode in detail, are generally available six weeks (air transport) to six months (freight transport by road) after the end of the reference month. Therefore, new and digital data sources were analysed for the purposes of the transport index and their suitability for the envisaged transport index (timeliness, availability and accuracy) was checked.
In view of the conflicting goals of timeliness and information content, the following indicators have been chosen to represent the respective mode of transport:
- Road transport: truck toll mileage index (BALM and the Federal Statistical Office)
- Rail transport: train path kilometres booked in the German rail network (DB Netz AG)
- Air transport: air freight handled at selected German airports (German Airports Association)
- Inland waterways transport: number of freight vessels berthing in nine selected German inland ports
- To be included - maritime transport: freight handling / number of freight vessel movements in German sea ports (national single window of the Federal Waterways and Shipping Agency)
The rapid availability of the individual indicators for the various transport modes enables the monthly experimental calculation of the transport index 30 days after the end of the reference month at the latest and makes it possible to meet the timeliness target.
The provisional transport index is based on the weights assigned to the subindices for the individual transport modes (not yet including maritime transport) in accordance with the modal split of the Federal Environment Agency, after seasonal adjustment and normalisation to 2019, the year before the coronavirus pandemic. The modal split indicates each transport mode’s share of the total freight transported, measured in terms of the transport performance. In 2018, road transport accounted for roughly 73.4%, rail transport for 19.5%, inland waterways transport for 6.9% and air transport for 0.2%.
The following chart shows how the provisional transport index and its subindices have developed (excluding maritime transport):
First provisional results (Table 1) show strong correlations between the transport index and selected short-term indicators such as the production index of manufacturing and underline that the index is generally suited as an additional experimental short-term indicator. Direct comparison with the existing truck toll mileage index shows that the transport index is a further improvement, however, as things stand now, only a minor one. More research is being conducted in this sphere.
| Index | Correlation1 with transport index | Correlation1 with truck toll mileage index |
|---|---|---|
| 1: Correlation analysis based on seasonally adjusted rates of change on the previous month covering the period from January 2016 to October 2020. | ||
| PI manufacturing | 0,93 | 0,91 |
| PI industry, excluding construction | 0,92 | 0,91 |
| PI intermediate goods | 0,80 | 0,79 |
| PI capital goods | 0,90 | 0,88 |
| PI consumer durables | 0,84 | 0,82 |
The transport index is still under development. It is intended to incorporate maritime transport into the transport index provided that it is suited for that purpose. Alternative weights will be applied to the subindices of the individual transport modes and studied; the search for new data sources and their analysis will continue. It will also be explored whether the subindices of the individual transport modes can be used as early indicators for official transport statistics.
In addition to the truck toll mileage index, the transport index (not including maritime transport) will initially be published monthly on this page as part of the experimental statistics (EXSTAT) offered by the Federal Statistical Office.
A detailed project report on the transport index concept, design and methods together with information on the selection of indicators and analyses of the suitability of the transport index as a short-term economic indicator is provided here.