Statistical processing

Source data

The statistics are based on three sources:

• Monthly reports from major Danish ports (with an annual throughput of at least 1 million tonnes of goods) on each port call of freight vessels or cruise ships, cf. information for data providers (in Danish only)
• Annual reports from minor traffic ports on calls of vessels, cruise passengers and throughput of goods, cf. information for data providers (in Danish only)
• Monthly reports from passenger ships and ferry lines on transported vehicles, passengers and goods, cf. separate documentation of statistics and information for data providers (in Danish only)

The tables on investments and on accidents are based on data from respectively the National Accounts and from the Danish Maritime Authority.

Frequency of data collection

Data are collected monthly from major ports and passenger ships and ferry lines and published quarterly.

Data on minor ports are collected annually and published in conjunction with statistics on major port annually.

Data collection

Data on both major and minor ports are through the joint public data collection portal, http://www.Virk.dk. Information for data providers are available at Statistics Denmarks website

• Information for data providers for major ports (in Danish only)
• Information for data providers for minor ports (in Danish only)

Data validation

Collected data are validated for use of correct coding and classification and validated at both micro and macro level for the development compared to previous data.

Data compilation

Quarterly statistics consists of input from two sources: Transport in major ports and 'Transport by Passenger and ferry lines*. From the latter only the goods transport on ferries are included.

Both statistics are compiled with the same detail except goods classification. All goods from ferry transport are classified as Ferry goods.

Data are checked for doublets on both port calls and goods transactions. Negative data lines that neutralizes erroneous data lines are handled.

In some cases the weight of goods in ferry transport are imputed based on the number of transported goods vehicles. It is the case when the data provider have no information on the weight of goods but only on the number of goods vehicles. The imputation is based on reports where all information is provided.

No enumeration is done since the coverage of the quarterly statistics is defined as ports with annual through-put of at least 1 mill. tonnes and all these ports report. The annual statistics has complete coverage for all ports.

Adjustment

Adjustments are made in the type of vessel if the reported type is contradictory to the type of goods.