If Type of data collection = Census => The division between the number of respondents who supplied data in response to the census (achieved no.) and the frame population number. Must be present as a percentage (%).
If Type of data collection = probability sample survey OR Non-probability Sample survey => The division between the number of respondents that supply data (and not, for instance, the number of questionnaires sent out, or number of companies contacted) (Achieved sample no) and the frame population number. Must be present as a percentage (%).