The absence of virtually any reliable current demographic data has not prevented national and international bodies from generating estimates and projections of population and population growth in Nigeria. The World Bank estimate of Nigeria's 1990 population was 119 million, with an estimated annual growth rate of 3.3 percent. Although other sources differed on the exact figure, virtually all sources agreed that the annual rate of population growth in the country had increased from the 1950s through most of the 1980s. The government estimated a 2 percent rate of population growth for most of the country between 1953 and 1962. For the period between 1965 and 1973, the World Bank estimated Nigeria's growth rate at 2.5 percent, increasing to 2.7 percent between 1973 and 1983. Projections about the population growth rate were uncertain, however, in view of questions concerning the accuracy of Nigerian census statistics.
This increase was typical of most of sub-Saharan Africa, where growth rates increased steadily throughout the post-World War II period. The key to decelerating the rate of population growth would be a sharp decline in the fertility rate, which is defined as the average number of children a woman will bear in her lifetime. Considered the second stage of the demographic transition process, it was well under way in 1990 in most other developing regions of the world, except for the Islamic nations of the Middle East. Few African countries, however, had experienced any substantial fertility decline, and the overall fertility rate for sub-Saharan Africa was estimated as 6.5 in 1983.
Any decline in the population growth rate in Nigeria or the rest of sub-Saharan Africa was expected to depend on the balance between the demand for smaller families and the supply of birth control technology. Urbanization (especially when full households, rather than just males, are involved) was likely to be the most powerful factor leading to a decline in