Nevertheless, the population density in the 32 states of the union varies considerably, ranging from very low rates in the states of Baja California Sur, Chihuahua, Sonora, Campeche, Durango and Coahuila, which each have less than 15 inhabitants per square kilometre, to high densities in the Federal District and the State of Mexico where there are 5,587 and 571 inhabitants per square kilometre, respectively. This diversity is derived from the significant differences both in population and in the surface area of the states. The population is concentrated in large urban centres and is also scattered in smaller towns. In 1997, Mexico had 115.9 doctors, 181.9 nurses and 80.5 hospital beds per 100,000 inhabitants. Mexico's long tradition of official anticlericalism ended in 1991 with the passage of constitutional changes granting legal status to religious institutions and allowing parochial schools.
Protestants represent a small but growing minority in Mexico.
The prevailing and official language is Spanish, which is spoken by the great majority of the population. Successive governments have instituted educational programs to teach Spanish to all Indigenous members of the population. Crude oil production equalled three billion barrels a day. 9.254 million telephone lines were also in service. Fertility of the soil.