• Data reference period
• Place of residence (Portugal)
• Age group

• INTERNET (www access):  The connection to the set of global computer networks interlinked by the TCP/IP protocol (Transmission Control Protocol/Internet Protocol), where data and service servers are located (FTP, WWW, email, etc.).
• AGE GROUP:  The age interval in years to which a person belongs at the time of reference .
• REFERENCE PERIOD:  The length of time for which data are collected, e.g. a specific day, month or year.
• RESIDENT POPULATION:  The persons who regardless of the fact that at the moment of observation ' 0:00 a.m. of the reference day ' are present or absent in a given housing unit, this unit being where they live during most of the year with their family, or where they have all or most of their belongings.

(Persons aged between 16 and 74 years old using Internet in the 12 months prior to the interview / Residente Population aged between 16 and 74 years old)*100