Question

what is the growth of population?Explain the two ways by which we can express population change.

Answer 1

200 years ago there were less than one billion humans living on earth. Today, according to UN calculations there are over 7 billion of us. Recent estimates suggest that today's population size is roughly equivalent to 6.5% of the total number of people ever born. This is the most conspicuous fact about world population growth: for thousands of years, the population grew only slowly but in recent centuries, it has jumped dramatically. Between 1900 and 2000, the increase in world population was three times greater than during the entire previous history of humanity—an increase from 1.5 to 6.1 billion in just 100 years.

How the world population is changing is of great importance for humanity’s impact on the Earth’s natural environment, but it also gives reasons to hope for a good future. This is because we have a bigger team of better educated people who can contribute to the solutions that improve global well-being.

A picture of the world population in the very long-run shows extremely rapid growth. Indeed, for a long time the world population grew at an increasing rate. However, if we focus on the last couple of decades, we see that this pattern no longer holds, as the annual rate of population growth has been recently going down. 1962 saw the growth rate peak at 2.1%, and it has since fallen to almost half. A long historical period of accelerated growth has thus come to an end.

Answer 2

The Growth of population is the change in the number of inhabitants of a country during a specific period (mostly during 10 years).
The growth in population can be expressed in two ways
(i) Absolute numbers It is the magnitude of increase of population in a year or decade. It is obtained by subtracting the earlier population from the later population.
(ii) Annual growth rate It is the rate of increase of population. It is measured in per cent per annum.