The above official link has many sections. Here is the link for the official language poll ("Enquesta d’usos lingüístics de la població 2008"), which includes m

The above official link has many sections. Here is the link for the official language poll ("Enquesta d’usos lingüístics de la població 2008"), which includes mother-initial/identification/habitual language details (official data): http://www.idescat.cat/cat/idescat/publicacions/cataleg/pdfdocs/eulp2008.pdf http://www.idescat.cat/cat/idescat/publicacions/cataleg/pdfd... "Initial language" (page 45): Catalan: 31.6%, Spanish: 55%. "Identification language" (page 48): Catalan: 37.2%, Spanish: 46.5% "Habitual language" (page 51): Catalan: 35.6%, Spanish: 45.9% Edit: in my first comment in this thread I spoke from memory. Also, the data from the 2013 poll (official data): https://www.idescat.cat/cat/idescat/publicacions/cataleg/pdfdocs/eulp2013.pdf https://www.idescat.cat/cat/idescat/publicacions/cataleg/pdf... "Initial language" (page 45): Catalan: 31%, Spanish: 55.1%. "Identification language" (page 46): Catalan: 36.4%, Spanish: 47.5%. "Habitual language" (page 49): Catalan: 36.3%, Spanish: 50.7%.