Guanajuato is one of the smallest states in Mexico, and also one of the most densely populated with 4’893,812 inhabitants, which corresponds to 152 persons per square kilometer, this without taking into account that 42% of the state population lives in the urban areas of León, Irapuato and Celaya. The last 2005 census reveals a very young population: 60% are under 30 years of age. Since 1950 the state shows a constant population increase. Life expectancy is 75 years. Guanajuato has a high migration rate to the United States: 35 migrants out of every 1000 inhabitants. The average education is 7.2 years. 50% of the population over 15 years old, has not finished primary school. 96% of the people say they practice the Catholic religion, ranking the state as the most catholic in the country. It is the state with the smallest indigenous population. Only 0.2% of the Purépechas, Pames, Guamares and Guachichiles ancestors speak an indigenous language. The tribes that still exists are the Chichimeca Jonaz, Otomí, Mazahua and Purépecha