Swiss automatic road traffic counts (SARTC)
Since 1961, the Swiss Federal Roads Authority has been operating a network of permanent automatic traffic counting stations on the country's most important thoroughfares. 330 such stations were in operation as of the end of 2009.
The map below shows the road network and the locations of the counting stations.
The ultimate goal is to record all traffic movements by direction and time (hours). The two most important criteria for evaluation are average daily traffic volume and average weekday traffic volume.
- Average daily traffic volume
Here an average figure is calculated for 24-hour traffic volumes on every day of the year. For roads that are closed during winter, statistics are only recorded for the period during which they are open.
- Average weekday traffic volume
Here an average figure is calculated for 24-hour traffic volumes on all weekdays (Monday to Friday) except public holidays. For roads that are closed during winter, the same method applies as for average daily traffic volume.
- Data collection: vehicles are detected and counted using induction loops that are integrated into the road surface and linked to counting devices.
- Data transmission is carried out daily via an automatic call-up system.
- Validation of data is carried out in three steps: daily, monthly and annual.
The data obtained are also used for making other detailed calculations, e.g. by period and direction, average volumes (daily, monthly, annual, periodical), peak levels
The processed data are published in the form of monthly and annual bulletins. The annual road traffic count report, which is published separately, has also been available on CD-ROM since 1997.