Documentation of statistics: Business Services in the Sector for Market Research and Public Opinion Polling
Survey data is grossed up in part by including information from administrative sources on the VAT turnover in the reference year for the entire population.
https://www.dst.dk/en/Statistik/dokumentation/documentationofstatistics/business-services-in-the-sector-for-market-research-and-public-opinion-polling
Documentation of statistics