The population of Bolivia in 2003 was estimated by the United Nations at 8,808,000, which placed it as number 84 in population among the 193 nations of the world. In that year approximately 4% of the population was over 65 years of age, with another 40% of the population under 15 years of age. There were 99 males for every 100 females in the country in 2003. According to the UN, the annual population growth rate for 2000–2005 is 1.89%, with the projected population for the year 2015 at 10,831,000. The population density in 2002 was 8 per sq km (21 per sq mi). Three-fourths of the total population lives on the Altiplano or in the western mountain valleys; the southeastern lowlands are sparsely populated.
It was estimated by the Population Reference Bureau that 63% of the population lived in urban areas in 2001. The administrative capital city, La Paz, had a population of 1,439,000 in that year. Santa Cruz, a departmental capital, had a metropolitan population of 1,110,000. Sucre, the legal and judicial capital, had 152,000. Other important departmental capitals include Cochabamba, 377,259; Oruro, 195,239; and Potosí, 114,092. According to the United Nations, the urban population growth rate for 2000–2005 was 3.0%.