THE growth of cities will be the single largest influence on development in the 21st century, with urban populations increasing much faster in developing countries, the UN Population Fund (UNFPA) states in its 1996 report.
The world's current population of 5.8 billion people includes 2.6 billion city dwellers, 1.7 billion of whom live in developing countries, the report said. With yearly births of 86 million projected until 2015, world population will pass the six billion mark in 1998.
The increase has been exponential, the UNFPA said it took 123 years for world population to increase from one billion to two billion, then succeeding billions took 33 years, 14 years and 13 years. The next billion is expected to take 11 years.
"During the remaining years of this critical decade, the world's nations, by their actions or inactions, will choose their demographic future" the report said.
Within 10 years, more than half the people in the world will be living in cities, and nearly all the urban population increase will occur in developing countries. They would account for 92.9 per cent of a 2.06 billion increase in urban numbers between 1970 and 2020.
Currently, two out of three urban dwellers live in developing regions. By 2015 it would be more than three out of four, and by 2025 nearly four out of five the report forecast.
"Much of this growth will come in the world's poorest countries, and many of the new urban dwellers, particularly women and their children, will be among the poorest people in the world", it added.
The report recorded low yearly birth rates in Europe, North America and Japan at 0.1 per cent, 0.9 per cent and 0.2 per cent respectively. Oceania, Latin America and Asia were close to the world average of 1.5 per cent at 1.4, 1.7 and 1.5 per cent, respectively.
Africa, however, has a record 2.7 per cent annual birth rate with a dozen or so countries set to double their populations within a generation. In 2025, China is projected to be still the most populous nation with 1.5 billion people, followed by India with 1.3 billion people, though the yearly birth rate would be 1 and 1.8 per cent, respectively.
UN population projections for 2015 range from a low of 7.10 billion to a high of 7.83 billion worldwide. "The difference of 720 million people in the short span of 20 years is nearly equivalent to the current population of Africa", the report notes.
By 2050, the low projection shows a world population of 7.9 billion people and the high projection a population of 11.9 billion.
In 1950, there were 83 cities or city systems with populations of more than one million, 34 of them in developing countries. Now, there are more than 280, a number expected to almost double by 2015.
The report commented that the urban future "carries many risks for the physical environment and natural resources, for social cohesion and individual rights, but it also offers vast opportunities. The experience of large cities as concentrations of human creativity and the highest forms of social organisation suggests that the future will open new avenues for human development.
Cities provide capital, labour and markets for entrepreneurs and innovators at all levels of economic activity, UNFPA said.