Annual

Data collection is via the internet with the option of sending in a paper version of the questionnaire.

Local unit (of an enterprise)

Since 2013, about 8,500 establishments are interviewed each year.
 The sampling method is as follows:
- Completeness for establishments of 250 employees or more and for strata sizing less than 10 establishments;
- For other strata: a survey optimised by a Neyman allocation (on energy consumption), with stress on the precision of estimates by activity.
From the EACEI 2013, the sample frame of EACEI is drawn from the new statistical Sirus directory (this directory is used as a frame for all thematic surveys). This change has led to a sharp increase in the number of units belonging to the scope of the survey between 2012 and 2013 : this fact impacts the results level