The data comes from the construction survey portion of the Business and Consumer Survey conducted by DG ECFIN. The construction survey is largely qualitative. The main questions refer to an assessment of recent trends in production, of the current levels of order books and stocks, as well as expectations about production, selling prices and employment. In addition, the survey also provides on a quarterly basis capacity utilization data which is not reported in conventional statistics.
Six surveys are performed on a monthly basis in:
Additional questions may be asked on a quarterly basis, as well as bi-annual questions about investment in the manufacturing sector. The types of questions asked for each section are:
The monthly confidence indicators are calculated for industry, services, construction, retail trade, consumers and financial services. The economic sentiment indicator is calculated based on certain questions from industry, services, construction, retail trade and consumers
For more detailed info please refer to: http://ec.europa.eu/eurostat/cache/metadata/en/ei_bcs_esms.htm