Population:
4,012,809
note: estimates for this country explicitly take into account the effects of excess mortality due to AIDS; this can result in lower life expectancy, higher infant mortality, higher death rates, lower population growth rates, and changes in the distribution of population by age and sex than would otherwise be expected (July 2009 est.)

Age structure:
0-14 years: 45.9% (male 927,599/female 915,540)
15-64 years: 51.2% (male 1,021,975/female 1,034,119)
65 years and over: 2.8% (male 46,687/female 66,889) (2009 est.)

Median age:
total: 16.8 years
male: 16.6 years
female: 17.1 years (2009 est.)

Population growth rate:
2.754% (2009 est.)

Birth rate:
41.37 births/1,000 population (2009 est.)

Death rate:
12.01 deaths/1,000 population (July 2009 est.)

Net migration rate:
-1.82 migrant(s)/1,000 population (2009 est.)

Urbanization:
urban population: 61% of total population (2008)
rate of urbanization: 2.7% annual rate of change (2005-10 est.)

Sex ratio:
at birth: 1.03 male(s)/female
under 15 years: 1.01 male(s)/female
15-64 years: 0.99 male(s)/female
65 years and over: 0.7 male(s)/female
total population: 0.99 male(s)/female (2009 est.)

Infant mortality rate:
total: 79.78 deaths/1,000 live births
male: 85.29 deaths/1,000 live births
female: 74.1 deaths/1,000 live births (2009 est.)

Life expectancy at birth:
total population: 54.15 years
male: 52.9 years
female: 55.43 years (2009 est.)

Total fertility rate:
5.84 children born/woman (2009 est.)

HIV/AIDS - adult prevalence rate:
3.5% (2007 est.)

HIV/AIDS - people living with HIV/AIDS:
79,000 (2007 est.)

HIV/AIDS - deaths:
6,400 (2007 est.)

Major infectious diseases:
degree of risk: very high
food or waterborne diseases: bacterial and protozoal diarrhea, hepatitis A, and typhoid fever
vectorborne disease: malaria and African trypanosomiasis (sleeping sickness)
animal contact disease: rabies
water contact disease: schistosomiasis (2009)

Nationality:
noun: Congolese (singular and plural)
adjective: Congolese or Congo

Ethnic groups:
Kongo 48%, Sangha 20%, M'Bochi 12%, Teke 17%, Europeans and other 3%

Religions:
Christian 50%, animist 48%, Muslim 2%

Languages:
French (official), Lingala and Monokutuba (lingua franca trade languages), many local languages and dialects (of which Kikongo is the most widespread)

Literacy:
definition: age 15 and over can read and write
total population: 83.8%
male: 89.6%
female: 78.4% (2003 est.)

School life expectancy (primary to tertiary education):
total: 9 years
male: 10 years
female: 8 years (2003)

Education expenditures:
1.9% of GDP (2005)