The Structure of Earnings Survey (SES) provides detailed and comparable information on relationships between the level of hourly, monthly, and annual remuneration, individual characteristics of employees (sex, age, occupation, length of service, highest educational level attained), and their employer (economic activity, size, and economic control of the enterprise).
The data collection is based on Council Regulation (EC) No. 530/1999 of 9 March 1999 concerning structural statistics on earnings and on labour costs and Commission Regulation (EC) No. 1738/2005 amending Regulation (EC) No. 1916/2000 as regards the definition and transmission of information on the structure of earnings.
Methodological description of survey
The SES is a four yearly survey and was carried out for the first time in 2002.
The target population of this survey is enterprises employing 10 or more persons and operating in NACE Sections B to S. This implies that relatively all types of economic activities are included in the target group except for agriculture and fishing, activities of households as employers, undifferentiated goods and services-producing activities of households for own use and activities of extra territorial organisations and bodies (NACE A, T, U). Data collected for this survey includes a demographic and socio-economic profile along with an earnings profile for a subsection of employees working within the primary unit which are selected for this enquiry. All information is subsequently grossed up to represent all employees working within companies employing 10 employees or more.
A 2-stage sampling mechanism is used for this survey. The primary sampling unit (i.e. the enterprise) is selected using stratified sampling at NACE 2 digit level and size class. The secondary sampling unit (i.e. employees) is selected via a simple random strategy within each enterprise.
The questionnaire is sent by email and in cases when emails of enterprises are not available, the questionnaires are sent by post. For non responding units, a number of interviewers are also employed to assist respondents compile this data.
Accuracy and reliability of data
Information on the accuracy and reliability of data can be viewed in a dedicated metadata report available on the NSO’s metadata website.
Timeliness and punctuality of data
SES data is submitted to Eurostat within a period of 18 months from the end of the reference year.
Accessibility and clarity of data
Results have not been yet made available at a national level. However, main results from this survey can be obtained from Eurostat’s online database.
A quality report is compiled and sent to Eurostat every 4 years following data collection and a similar report is available on the NSO’s metadata website.
Coherence and comparability/consistency of data
National concepts applied for SES are in line with European Union concepts since the definitions outlined in Commission Regulation 1738/2005 are applied in the local context. However comparability over the years may be affected by changes in classifications. For coding of economic activity, the NACE Rev. 2 classification has been adopted for SES 2010. Similarly for coding of occupations, ISCO 08 has been adopted since SES 2010. Previously the NACE Rev. 1.1 and ISCO 88 were used. The classification of education was revised from ISCED 1997 to ISCED 2011 as from SES 2014.
In terms of the statistical units which are covered for SES, data is collected from legal units which are recognized as having autonomous management and an independent accounts system. At NUTS 1 level, the whole country is represented; therefore information could be collected from enterprises which are recognized to be legal units by the Business Register. Over the years, changes in the target population were also employed. Up to year 2010, enterprises under section O were excluded from the population, while in 2014 such enterprises were introduced for the first time. The inclusion of enterprises under section O is still option as per Eurostat’s regulation, however this is covered by most countries.
Variations between National Accounts and the Structure of Earnings Survey estimates are the result of the micro business effect (under 10 effect) which is taken into account in the National Accounts averages but is missing in the SES estimate. The largest difference in earnings relates to NACE S (Other service activities). Upon additional checks with National Accounts, the change between the two estimates is deemed to be the result of seasonal changes in employment since the sector increases its employment during the summer months and hence this matter lowers the per capita value when spread across one year.