Annual estimates:

• For employed people, the data come from social declarations made by employers (DADS and DSN), supplemented by data from the Information System on Public Service Employees (Siasp) and those of individual employers.
• For self-employed, the sources used are the files of the Mutualité Sociale Agricole (MSA) for those affiliated to the agricultural regime and the files of the Agence centrale des organismes de sécurité sociale (Acoss) for the others.

Quarterly estimates: the data come from the contribution summary slips (BRC) or nominal social declarations (DSN) made by employers, and payroll files for civil servants.

Monthly

Frequency of data collection: monthly reporting of companies' social declarations and payroll files of the State employees.

Before 2007, Annual Employment Estimates were produced from population censuses, which made it possible to calculate "reference" employment levels (for example: employment at the end of 1989 for the 1990 census, end of 1998 for the 1999 census). Between two censuses, annual employment trends were estimated using various administrative sources, from which growth rates applied to the previous year's employment levels were derived. In doing so, it was assumed that there was constant multi-activity between two censuses.

Starting in 2007, the annual employment estimates process synthesizes every year the various sources on employment, salaried and non-salaried. A certain number of processes are carried out in order to obtain a homogeneous measurement of employment between year N and year N-1 : automatic adjustments and validation of headcounts, of their geographical location and activity classification, manual adjustments and validation as part of an appraisal campaign, by comparing when necessary the data by establishment with the quarterly source "Epure" (on the salaried field). This first vintage made it possible to determine a new "base level" of employment.

Between the 2007 and 2018 vintages, the process was then used to measure changes in employment between two successive years. That is:

• Employment levels at the end of 2007 were considered fixed ("base level");

• Each campaign made it possible to measure the N-1 / N evolution rates of salaried employment by sector of activity A88 and department, and of non-salaried employment by sector A5;

• These rates of change were applied to the results of the previous year ("chaining" from the base level) to calculate the levels of the year N.

The 2019 vintage has allowed for a "rebasing" of the Annual Estimates: employment levels have been recalibrated to those observed in the statistical sources derived from social declarations, whereas successive chaining since 2007 had led to some drift. Levels before 2018 have been "back-calculated", i.e. recalculated to preserve past trends. The series published are therefore still "break-free", even after the rebasing.

Employment levels by employment zone are computed in a similar way, but then adjusted to an "encompassing area" (usually the region), in order to ensure the consistency of the different geographical levels. The male/female and age group distribution of salaried employment is calculated only on the source data for year N and applied directly to the Employment Estimates for year N.

All quarterly series released are seasonally adjusted, using the X-13 Arima procedure in JDemetra+ software.

The seasonal adjustment models are reviewed once a year for the first quarter release. The coefficients of these models are re-estimated each quarter.