• Data reference period
• Place of residence at Census date [2021] (NUTS - 2013)
• Sex

• ILLITERATE:  Person aged 10 or over who cannot read or write, i.e. who is unable to read and understand a written sentence or write a complete sentence.
• PLACE OF USUAL RESIDENCE:  Place in which a person normally spends the daily period of rest (regardless of temporary absences for purposes of leisure, holiday, visits to friends and relatives, business, medical treatment, or others) and where the person lives or intends to live for the most part of the year, taking the last 12 months as reference.
• SEX:  Biological and physiological characteristics that define men and women.
• RESIDENT POPULATION:  Set of persons who, regardless of being present or absent in a given housing unit at the moment of observation, have lived in the place of their usual residence for a continuous period of 12 months prior to the moment of observation, or have arrived to the place of their usual residence during the period of 12 months prior to the moment of observation, with the purpose of living there for a year, at least.
• REFERENCE PERIOD:  Period to which the information refers and which may be a specific day or a time interval (month, fiscal year, calendar year, among others).

(Resident population with 10 and more years old ("It does not know to read or write")/ Resident population with 10 and more years old)*100