The islands of Ibiza and Formentera has quadruplicated their population in the last 160 years, according to the data done by the National Institute of Estadi'stica (INE). The growth of the number of homes has been much more spectacular, but the biggest changes has been from halves of XX century, with the tourist boom, since there has been a tendency to the loss in the number of children of the families. The fact that the population has grown more although the families have less children because the increase of the immigration produced the result of the tourist phenomenon, in which the islands happen to be lacking manual labor towards other regions or foreigners, there for has been receiving workers of services, Spanish as as much foreign.

The tourism also has caused the increase of European population that has established itself in the islands as a second residence or his first in the case of older people and this phenomenon also affects the population data. The city of Ibiza and municipioo of Sant Antoni have had a uninterupted growth during the studied period. First it had 5,118 inhabitants in 1842 and 34.826 in 2001, and the second it has happened from 3,539 to 15,081 in the same dates. Santa Eul