Distribution of Flemish Twitter users in Belgium 2015, by age

The source explains that: "In the period August to September 2015, 2,181 individuals have completed the survey. 1,532 respondents (or 70.2 percent of the total sample) were collected offline by means of (tablet) computer-assisted personal interviews (CAPI) or paper and pencil interviews (PAPI). 649 respondents (or 29.8 percent) filled out the survey online (computer-assisted web interview or CAWI)."

Furthermore, the source states that: "digiMeter provides a snapshot view of the adoption and use of media and ICT. It is based on the self-reporting of media consumers. As such, the results should be interpreted as the perception respondents have of their own media consumption. The methodology does not allow for assumptions on the effective media reach."

* The source does not specify the number of respondents for this particular question.