The category of "indigena" (indigenous) can be defined narrowly according to linguistic criteria including only persons that speak one of Mexico's 89 indigenous languages, this is the categorization used by the National Mexican Institute of Statistics. It can also be defined broadly to include all persons who self identify as having an indigenous cultural background, whether or not they speak the language of the indigenous group they identify with. This means that the percentage of the Mexican population defined as "indigenous" varies according to the definition applied; cultural activists have referred to the usage of the narrow definition of the term for census purposes as "statistical genocide".