According to the paragraph, if the national income per head falls, …….

Demography, the size of population, the speed at which it changes and its age structure, is an important factor in determining how a country' s economy will perform and what economic policies a government should follow. For example, in a country where the population is growing very fast, the economy has to grow quickly if the income per head is not to fail. In a country like South Africa, where the population is rising by about 2.7 per cent a year, politicians are worried about producing enough extra national income to at least correspond that level of increase. In Britain, however, the population has grown by less than 2 per cent over the last 10 years. Therefore almost all the economic growth in Britain during that time has meant higher average per head, even if the distribution of income is unequal.