According to a 1992 estimate, the national population is about 54 million.
It is most densely concentrated in the highland areas.
Almost 90 percent of the people live outside cities.
More than 45 percent of the people are 15 years of age and younger.
Both birth and death rates are high.
The average life expectancy at birth is about 45 years for males and 49 years for females,
among the world's lowest