• Data reference period
• Geographic localization (Portugal)
• Employment size class

• ENTERPRISE:  Legal entity (natural or legal person) that is an organisational unit producing goods or services, which benefits from a certain degree of autonomy in decision-making, especially for the allocation of its current resources. An enterprise carries out one or more activities at one or more locations.
• Electronic mail:  System that allows the sending of messages by computer inserted in communications networks or other communications equipment. E-mail is a computerized version of the services of internal correspondence or postal services. The messages may include voice, graphics, images and other information.
• STAFF:  The persons who during the reference period participated in the business of the enterprise/institution, regardless of the duration of this participation, under the following conditions: a) staff bound to the enterprise/institution by na employment contract, receiving remuneration in return; b) staff which has ties to the enterprise/institution, who, for not being bound by na employment contract, does not receive regular remuneration for the hours worked or the labour supplied (e.g. owner-managers, unpaid family workers, active members of cooperatives); c) staff with ties to other enterprises/institutions who worked at the enterprise/institution and receive remuneration directly from it; d) persons in the above situations, absent for a period of no more than one month due to holidays, labour dispute, vocational training, as well as disease and occupational accident. The following persons are not considered to be staff: i) those in the situations described in a), b), and c) above and who are absent for a period of over one month; ii) workers with ties to the enterprise/institution who moved to other enterprises/institutions, receiving remuneration directly from the latter; iii) workers in the enterprise/institution whose remuneration is borne by other enterprises/institutions (e.g. temporary workers); iv) self-employed workers (e.g. service providers, that use the so-called 'recibos verdes', which is the popular name of the receipt form).
• REFERENCE PERIOD:  The length of time for which data are collected, e.g. a specific day, month or year.

[Enterprises with 10 and more persons employed using e-mail/ Enterprises with 10 and more persons employed (NACE Rev. 2 C, D and E, F, G, H, I, J, K, L, M, N, S)]*100