Madagascar has over 15 ½ million inhabitants. The population density is about 26 inhabitants per km ². To the west it is just 2 inhabitants per km ² . The average population growth is about 3% per year. This means that the population doubles approximately once every 22 years. This high growth rate is due to the fact that the average parent gets 5.84 children and families with more than 10 children are quite normal. The average life expectancy is not very high, almost 55 years. Almost 80% of the population still lives in rural areas, around 20% live in the cities. The migration to the big cities is large and it is expected that in 2015 about 40% of the population will live in the cities. The capital Antananarivo currently has nearly 1.1 million residents. The entire metropolitan area has about 3.6 million inhabitants. Other large cities are Toamasina (127,000 inhabitants), Fianarantsoa (130,000) and Antsirabe (120,000). The Madagassiër are predominantly of Malay-Indonesian origin and to a much lesser extent, black and Arab elements are present. Approximately 1% of the population consists mainly French, Comorezen, Indians, Pakistanis and Chinese. The traditional Malagasy population is divided into 18 tribes, mainly based on the borders of the former kingdoms rather than ethnic traits. Although some strains are clearly of Asian or African descent, the Malagasy population is generally a mix of different strains.