Ministry of Labour, Solidarity and Social Security

Office for Strategy and Planning

Praça de Londres, nº 2 3º

1049-056 LISBOA PORTUGAL

The Structure of Earnings Statistics 2018 in Portugal was obtained  through the combination of three sources:

(a) an administrative source which provides micro data on enterprises, local units and employees. It covers all the required information on monthly earnings and hours paid, as well as  the information characterizing the employee

(b) a  survey to collect the missing information, regarding the variables on an annual basis and also Social Security and Income taxes;

(c) a specific survey for public bodies of Sections P and Q of NACE Rev. 2, to collect all required information, monthly and annual, on employees and wages.

• for economic activities: Statistical Classification of Economic Activities in the European Community, Rev. 2 (2008) (NACE)
• for occupation: International Standard Classification of Occupations 2008 (ISCO-08) – pages 3-34
• for education: International Standard Classification of Education 2011 (ISCED 2011) - Section 9. (pages 71-72)
• for regions: Nomenclature of Territorial Units for Statistics, by regional level, version 2013 (NUTS)

 Sections B to S, excluding O (NACE Rev 2)

Statistical concepts and definitions are in line with the Commission Regulation (EC) No 1738/2005.

Local unit and employes with a employment contract,  working in the local unit and who received remuneration during October of 2018

Enterprises with at least 10 employees belonging to Sections B to S, excluding O (NACE Rev 2)

Portugal

2018 and the reference month of October

not applicable

The Structure of Earnings Statistics 2018 in Portugal was obtained through the combination of (a) an administrative source, in existence since 1981, which provides microdata on enterprises, local units, and employees, covering all the SES required information on monthly earnings and hours paid, as well as the information characterizing the employee, ; (b) a specific survey to collect the missing information, regarding the variables on an annual basis and also Social Security and Income taxes; (c) a specific survey for public bodies of Sections P, Q, R and S of NACE Rev. 2, to collect all required information, monthly and annual, on employees and wages.

1. Quadros de Pessoal (Lists of Personnel) – Annex A of the Unique Report

As most of the monthly information requested for Structure and Earnings Statistics is available in Portugal as a statistical output of an administrative source designated as “Quadros de Pessoal”, the data was used on the structure of earnings. To complete the information (mainly annual data) a specific sample survey was carried out.

Since 2009, Quadros de Pessoal is one of the annexes of the Unique Report, an administrative source integrating information on enterprises, local units, employment, vocational training, health and safety at work, strikes, etc.

This administrative source was created to monitor the law enforcement regarding the labor legislation and has been statistically treated since 1981, although it had previous legal existence. The statistical use was established by Decree nº 380/80, from September the 17th.

The legislation in force is the Law nr 7/2009, of February the 12^th, the Labour Code, and the regulation of the report is the “Portaria” nº 55/2010, of January the 21^st. As regulated, the enterprises have to provide all the information by electronic data transfer.

The variables collected relate to the enterprise or the local unit in the scope of SES are as follows:

• name and address (and consequently, regional location);
• main economic industry;
• size of the units in terms of the number of occupied persons and employees;
• collective agreements or administrative regulations existing in the units;
• form of financial control.

The variables related to each of the persons occupied in the reference month (October) are the following:

• social security code number;
• collective agreement or administrative regulation applied;
• occupation;
• occupational status (self-employed, employee, other);
• highest completed level of formal education;
• gender;
• date of birth;
• date of coming into the enterprise;
• type of employment contract;
• Full-time or Part-time;
• monthly value for basic pay;
• monthly value for all other regular payments, excluding overtime;
• monthly value of payments for overtime;
• monthly number of paid hours, excluding overtime;
• monthly overtime hours;
• normal (contractual) weekly hours of work.

2. Structure of Earnings Survey  2018

As some of the variables requested by Eurostat were not available through “Quadros de Pessoal”, a specific sample survey was carried out in order to collect the missing information. That information consisted mostly of annual data on earnings, annual days of holidays, other paid absences and social security payments, and income tax payments.

The scope of the survey covers industries comprised in Sections B to S, excluding O, of NACE Rev. 2 and employees in enterprises with 10 or more persons occupied.

The data collection was performed by 2 web questionnaires, one for “private” entities and the other for public bodies.

For the public part of NACE Rev. 2 Sections P and Q, there was no administrative information on employees with a public servants status. The sample was obtained from the registers of the Directorate General for Administration and Public Employment and the questionnaire addressed to public bodies collected all the variables specified in the implementation arrangements, either monthly or annual.

Sampling plan

Sampling design

Population

At the 1st stage, the population for this survey is the local units of the national territory, belonging to private sector enterprises with at least 10 employees, referring to economic activities defined in sections B to S of NACE Rev. 2, with the exception of class 94.91 (activities of religious organizations) and class 94.92 (activities of political organizations) and section O ( Public administration and defense; compulsory social security). Education (section P) and Human health and social work (section Q) activities include both private enterprises and public enterprises with 10 or more employees.

At the 2nd stage, the population consists of all employees in the local units.

Framework

The framework for this survey was built from the Business Register of Enterprises and Local Units of GEP / MTSSS, taking into account the conditions required for the universe of reference. The Business Register is based on the administrative source "Quadros de Pessoal," which reference period is the month of October of each year. The file of public enterprises with Education and Human health and social work activities from the Directorate General for Administration and Public Employment was used to complement the business register.

Drawing the Sample

Methodology for design and selection of the sample

Primary Units

The sample design considered in this survey involves a simple two-stage cluster sampling. At the first sampling stage, the clusters are the local units that are selected by stratified random sampling; employees are selected at the second stage by simple random sampling within each local unit selected at the first stage.

In the first stage, the primary units are defined by local units of enterprises with 10 or more employees of sections B to S, except O, of NACE Rev. 2. In the second stage, the secondary unit concerns the employees who belong to the local unit.

Overall size of the sample and breakdown by strata

The number of primary units to be selected for the private sector was determined for each of the regions defined by NUTS I (Continente, Região Autónoma da Madeira and Região Autónoma dos Açores). The size of these samples is based on a study that considered as a variable of interest the "monthly gain" of full-time employees and with full pay. To ensure a relative error not exceeding 'd', between the estimate and the real value of the variable of interest mentioned, and assuming a sample rate on the second stage, it was determined the number of primary units (m) according to the following expression:

Note that,

where,

M – number of local units in the population

N – number of employees in the population

i  - index of the local unit

N_i - number of employees in the local unit i

n_i - number of employees selected in the local unit i

j - index of employee

X_ij - monthly gross earnings of employee j of the local unit i

d - relative error

z_(1-α_/2)=1.96  quantile of order (1-α/2), a=0.05 of Z~N(0,1)

It was considered a confidence level of 95% and a relative error of 1.1% for Mainland and 5% for the Autonomous Regions. We assume a response rate in all NUTS I of 60%=r. The sample size was multiplied by a correction factor for non-response, mr=m/r. The sample size of the primary units according to NUTS I, was 12283 for the Mainland,1147 for the Autonomous Region of Açores, and 1206 for the Autonomous Region of Madeira.

The sampling rate in the second stage was established according to the dimension of the local unit and the previous SES survey.  

The allocation of the sample of primary units to the strata is developed from the decomposition of the universe of reference, through the intersection of variables: NUTS 2 (North, Central, Lisbon, Alentejo, and Algarve), the economic activity of the primary unit down to the level of division of NACE Rev. 2 and class size of the enterprise.

The class size of the local unit is defined based on the variable “number of employees" (10-19, 20-49, 50-99,100-249, 250-499, 500-999, and 1000 or +).

The allocation of the sample by the strata is done proportionally to the square root of the variable total number of employees (power allocation r=1/2). The number of primary units in the NUTS 2 i, economic activity j, class size of the enterprise k, the stratum h = (i, j, k), is given by:

where,

N_h  is the total number of employees in local units of stratum h;

m   is the sample size.

It was established that the minimum number of local units sampled in each stratum is four units in Mainland and eight units in Autonomous Regions.

Sample Selection

The sample selection of the local units within strata is made using a systematic sample with a random start.

In the second stage, the secondary units were selected by the respondent's primary unit according to the class size of the respective unit and month of birth of employees, as presented in the table below.

This criterion for selection took into account the uniform distribution of the months of the birth of the employees in the primary units. It was increased the number of months in the smaller units in order to ensure a more reasonable response rate.

The sample size was about 145980 employees for Continente, 9807 for Região Autónoma da Madeira and 8873 for Região Autónoma dos Açores.

The Table in Annex 1 Population and Sample presents the number of local units and the number of employees in the sampling frame, the sample size, and the net sample size.

Software

IBM SPSS version 25.0 - Complex Samples module was used to select the sample, in the estimation and to calculate the variance of the estimates.

Linkage of the two sources

The web application allowed the enterprises to select the employees' sample or to opt for the sample selected by the Office. The information on the local unit surveyed was presented on the screen and also the identification numbers of the selected employees. The enterprises filled in the required information.

If the respondent performed the selection (on the basis of the birth months, as specified on the explanatory notes), also the identification code was filled-in, to allow the linkage with the administrative source data.

In linking the information, the coherence of certain variables deriving from the two sources was checked (monthly and annual earnings, for example).

Final results were obtained after estimating procedures applied to data collected for the local units and employees in the sample. Variables such as economic activity, size class, and region were re-weighted based on the comprehensible information resulting from the 2018 “Quadros de Pessoal”.

Variables that had to be converted into Eurostat’s classifications

Collective agreement on pay covering the employees of the reporting unit - The type of collective labor regulations existing in Portugal and that can be identified through “Quadros de Pessoal” do not fit in exactly with the four categories specified at the Community level, although they were integrated in those categories after a specific analysis of the scope of all collective agreements. The types of agreements that can be isolated within the administrative source are briefly described as follows:

• Enterprise agreement - is signed by a single employer and by one or more trade unions;
• Collective enterprises agreement - is signed by two or more employers of an individual industry (not necessarily covering all enterprises of that industry) and one or more trade unions;
• Collective agreement - signed by one or more employer’s associations and one or more trade unions;
• Administrative labour regulation - reflects two kinds of situations: one, when the employees do not have a capacity for negotiation; the other, when there is a break in the collective negotiation between the partners involved. In either case the initiative of regulation belongs to the Labour Ministry.

Total number of persons employed in the reporting unit during the reference month - The total number of persons employed in the local unit, at national level, do not include trainees without an employment contract and voluntary workers. Only employees, active proprietors, family workers and co-operative active members are considered, but only employees were surveyed.

Highest completed level of education and training - this information, referring to formal education and collected in “Quadros de Pessoal” with greater desegregation for third level qualifications.

Type of employment contract - for this variable only three hypotheses were considered: indefinite duration contract, contract with a fixed term (fixed duration or completion of a certain task, return of an employee) and other contracts (active co-operative members, not specified situations). Apprenticeship contracts, corresponding to training contracts usually assuming a dual apprenticeship system, in the school and in the enterprise, are not covered by “Quadros de Pessoal” as the persons involved in this system are not considered employees, are not paid by the enterprise and for Social Security purposes also do not count as employees.

Reflection of absences on monthly earnings - three situations, concerning monthly earnings and hours paid for, can be isolated in “Quadros de Pessoal”, by analysing the individual information on normal weekly hours of work, monthly hours paid for excluding overtime and monthly basic wage pay. (a) The first situation corresponds to employees being paid the complete basic wage in the reference month (a deduction of three days pay is allowed) and consequently having filled in complete hours paid for; (b) then there can be employees who did not receive complete monthly basic wage and consequently have reduced hours paid for; (c) employees who have a contract with the enterprise in the reference month but who have not received any pay and have no hours paid for. For employees who did not receive complete pay during the reference month, the earnings were imputed using the hourly rate payment they had for the period they had worked and received payment, on the basis of the working time in the local unit.

Employees who did not receive pay during the reference month were excluded from the survey.

 According to the Regulation (every 4 years)

The process of collecting information is almost fully performed in electronic format

Variables surveyed

For the “private sector” survey, the variables included were the following:

Relating to the local unit:

• total number of employees (optional).

Relating to the employee:

• entitled number of days of paid holidays;
• period to which annual earnings correspond;
• total annual gross earnings;
• of which irregular bonuses, separated by bonus paid at fixed periods, profit sharing and other irregular bonuses;
• social security payments (by the employee);
• income tax payments.

For the public sector, all the variables were surveyed.

It was used a web survey. The validations were embedded in the electronic questionnaire and were executed before transmitting the questionnaire. The checks performed by the software were according to plausibility and variable coherence. Warnings and fatal errors are created when data is outside the predefined standards. Fatal errors prevent data sending. It cannot be overruled, except by the statistical staff with a specific password.

Upon arrival to the statistical office, warning checks were again performed and corrected, if it was the case.

Data is treated by the software IBM SPSS Statistics- version 25

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At national level, the main users are:

The Ministry of Labour, Solidarity and Social Security, for the analysis of wage formation, minimum wage regulation, labour regulation analysis and labour market analysis. The information required regards tabular data and micro data.

The portuguese Statistical Office, for the National Accounts, among others.

Research bodies of Universities, for specific studies and modelling.

The Bank of Portugal uses the micro data for research projects.

Employers’ associations and Unions, with relevance for data for labour negotiations. The information is provided on requirement, on tabular form.

There is no survey on the satisfaction of users regarding SES. Being the only source that provides micro data on the composition of earnings and employee’ variables, besides employer’s characteristics (with annual periodicity), this information is regarded by users as of the most utility.

see 5.3.1

All mandatory variables according to Commission Regulation (EC) No 1738/2005 are submitted.

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See coefficents of variation

Coefficient of variation

For further information on the calculation, find the attached file Coefficients of variation - calculation.

See also the attached document Coefficients of variation. Please take note that the coefficients of variation are not expressed in percentage.

Point treated in the sub-items

The information on activity, region and number of employees in the sampling frame is comprehensibly updated annually, with reference to the month of October of each year. The 2018 sample was selected using the 2018, as data for the administrative source is electronically transmitted. Due to the timely updating of the sampling frame, coverage errors for the private sector have no meaning.

The units for public sector do not have considerable changes in the short run.

The over coverage errors are due to non-active local units , local unit with less than 10 employees or misclassification regarding the nace group and size of the enterprise.They were assumed to be negligible since the sampling frame was constructed at the end of the reference period and all sources were used in order to specify the sampling frame. The over-coverage rate is about one percent.

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The form used for the administrative source is in place for 30 years, with some minor changes during this period. Enterprises are used to it and, with the comprehensible use of electronic data transmission, they have a better knowledge of the classifications involved.  

As the electronic data transmission does not allow for non-response for the variables needed for SES, and also the survey did not allow for non-response, the imputation rate for demographic variables and wages was 0.

Unit response rate for the survey – 64.6 % unit response rate, corresponding to 58.5 % of the expected employees in the sample.

The responses (local units and employees) were re-weighted on the basis of the final results of the administrative source (comprehensibly treated) of local units in the survey scope and of the actual number of employees in the surveyed unit.

The response rates for the variables monthly earnings and monthly hours paid, deriving from the administrative source, was 100%, as those are considered mandatory variables in that source. Also for annual earnings, obtained through the sample survey, the variable was mandatory and non-responses were not allowed.

As the electronic data transmission does not allow for non-response for the variables needed for SES, and also the survey did not allow for non-response, the imputation rate for demographic variables and wages was 0.

Social security taxes non-responses (obtained by the survey) were imputed on the basis of the standard social security tax supported by the employee (11 % of earnings for private sector and 14,5% for the civil servants entering the public service prior to 2007).

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The form used for the administrative source is in place for 30 years, with some minor changes during this period. Enterprises are used to it and, with the comprehensible use of electronic data transmission, they have a better knowledge of the classifications involved.  

As the electronic data transmission does not allow for non-response for the variables needed for SES, and also the survey did not allow for non-response, the imputation rate for demographic variables and wages was 0.

Regarding the monthly earnings, the rate of imputation (for employees that were not at work for part of the reference month and consequently did not receive complete earnings for that month) was 10 %. The imputation was made on the basis of the contractual hours per month and the earnings hourly rate for the period they had worked and had been paid during the reference month.

Regarding the monthly earnings, the rate of imputation (for employees that were not at work for part of the reference month and consequently did not receive complete earnings for that month) was 10 %. The imputation was made on the basis of the contractual hours per month and the earnings hourly rate for the period they had worked and had been paid during the reference month.

Not applicable

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7 months from the launching of the survey (December 2019) to the data transmission (3 July 2020)

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Data transmission was done with a 3 days delay.

see 7.2

No remarks

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The coverage, statistical units and definition of the common variables are identical to those used for the previous 1995, 2002, 2006, 2010 and 2014 SES.

The variable “payments for shift work” was introduced in the administrative source from the year 2009 onwards but was not available before.

The variable “payments in kind” was transmitted to Eurostat for the year 2010 (and not in 2006), although there are very few responses available. Expenses such as “company cars” when they exist, are not considered to be of personal use to the employee but as used in the service of the company.

 The data collection methodologies and procedures (administrative source combined with a specific survey to collect annual variables and information on income taxes and social security taxes, for the private sector) was also maintained.

Public institutions data was directly collected from the institutions for the year 2010 onwards, contrary to the year 2006, when they were estimated on the basis of an administrative instrument carried out for 2005.

see 8.2

Coherence with the National Accounts

The comparison of data was done using SES 2018 variable  B4.1 adjusted and from the 2018 National Accounts, wages and salaries (D.11) (current prices/per full-time equivalent employees.

Adjustments  for variable B4.1 were done in line with the instructions given in section 3.2.4 of the Implementing Arrangements 2018

Coherence SES 2018 – National Accounts 2018

Some of the reasons that can explain the differences by NACE, may lay on the differences in the definitions of the variables and also on the scope of the two sources: SES 2018 covers local units of enterprises with 10 or more employees and National accounts refer to the total sizes.

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 see 8.3

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The results of SES 2018 are disseminated by a Statistical Summary and a Publication (on the Internet Web site: Sínteses / Publicações - Gabinete de Estratégia e Planeamento (mtsss.gov.pt)

Additional information can be provided on request to the users, in table format.

There is no online database for the results of the SES 2018.

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Microdata can also be delivered on request, for research projects, after anonymization.

Respondents are not provided with results of the survey, only by request.

The publication contains a chapter on the concepts and methodologies used, together with illustrative texts and graphs.

In addition, a more detailed methodological document is also available on GEP and Statistics Portugal websites.

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No information

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No remarks