To ensure that the BARB panel properly represents the UK population, a range of data on the characteristics of television households are needed. These are derived from the establishment survey, a continuous survey involving approximately 53,000 household interviews a year, carried out, on behalf of BARB, by Ipsos MORI. The survey enables changes in the structure of the population to be reflected in the data that BARB produces. Establishment survey data is used continuously in the operation of the panel. Results from the survey are summarised in annual reports providing demographic information and data on television ownership for BBC and ITV/Channel 4 areas. The Network report is published quarterly. Aside from these reports, the establishment survey results are available to BARB users and BARB registered data processing bureaux in a data file. This allows a more flexible analysis, as well as more frequent reporting. Data is issued on a quarterly basis, with reporting possible for quarterly, annual or two-year time periods. If you are interested in accessing the data files, please contact BARB on 020 7024 8100. For more background information about the establishment survey, please see How we do what we do. The latest establishment survey reports are available below in pdf format to download with archive reports in the folders. To access the reports click onto the report title. Quarterly and Annual Network reports for the same report period may differ due to different sample base sizes. Annual reports are based on the last 12 month establishment survey sample compared to 3 months for quarterly reports.