The population of Congo, Republic of the in 2003 was estimated by the United Nations at 2,908,000, which placed it as number 132 in population among the 193 nations of the world. In that year approximately 3% of the population was over 65 years of age, with another 46% of the population under 15 years of age. There were 98 males for every 100 females in the country in 2003. According to the UN, the annual population growth rate for 2000–2005 is 2.57%, with the projected population for the year 2015 at 5,215,000. The population density in 2002 was 9 per sq km (24 per sq mi). Large portions of the Congo basin are basically uninhabited.
It was estimated by the Population Reference Bureau that 63% of the population lived in urban areas in 2001. At least four-fifths of the people live in the southern third of the country; the greatest concentration is in the Brazzaville area, while the northernmost region is sparsely populated. The capital city, Brazzaville, had a population of 1,187,000 in that year. Other large cities include Pointe-Noire, 387,774; Loubomo, 62,073; and Nkayi, 40,019. According to the United Nations, the urban population growth rate for 2000–2005 was 3.7%.
The prevalence of AIDS/HIV has had a significant impact on the population of REpublic of the Congo. The United Nations estimated that 7.2% of adults between the ages of 15–49 were living with HIV/AIDS in 2001. The AIDS epidemic causes higher death and infant mortality rates, and lowers life expectancy.