More than two-thirds of the islands' population is Creole (mulatto), and the remainder are European and black African. Apart from Portuguese, which is the official language, the inhabitants speak a Portuguese dialect called Crioulo. Most of the population is officially Roman Catholic, but a flourishing Protestant mission based in São Tiago has a church and schools on most of the islands. Many animist customs are still preserved. About three-fifths of Cape Verde's population is younger than 20 years of age. Many older inhabitants emigrate to seek work abroad, mostly in Europe, especially Portugal, and in Venezuela and Brazil. Of the more than 1 million individuals of Cape Verdean ancestry, less than half actually live on the islands.