The information is collected by means of a yearly questionnaire based survey where the farmers complete the questionnaire online. The answers are validated for non probable values.
Information on crops and the animals cattle and fur animals is collected from registers, and is thereby not reported by every single farmer.
The survey is a sample survey stratified by region, size and type of farming.
The information comes from the questionnaire, IACS, the livestock register and information from the fur animals farmers’ organisation.
In 2019 the sample had a size of 6.000 farms, about 25 per cent all farms in Denmark.
The sample is stratified by regions, size and type of farming (e.g. pig farms, cattle farms and plant production).
The survey is yearly.
The farmer reports the information on a web questionnaire on Virk.dk
Information on the survey can be found here: Information
The text is Danish.
The statistics go through an error detection process which falls into three steps:
The extrapolation into a total level takes place by obtaining certain known targets:
In case of non response the farm is excluded from the sample and the extrapolation is increased accordingly for stratum where non response occurs. The non-response is about 5-10 per cent, in 2018 4.1 per cent.
Imputation is normally not done in the farm structure census. If it nevertheless is done the method is to find a donor farm which has answered the question and is rather similar to the farms with a missing answer. One example could be use of water for irrigation where a farmer in the same region and having a similar composition of crops. Use of water for irrigation is not included in the survey every year.
In the survey 2019 the results for about 17.000 farms smaller than 25 hectares will be imputed.
No corrections are made besides what is described in data validation and data compilation.