How do we know that population growth is coming to an end?

Since 1950, the total number of children younger than 15 years of age increased rapidly, from 0.87 billion children to 1.98 billion today. The solid green and red lines in the visualization indicate the total number of children in the world. As we can see, we are not far away from the largest cohort of children that there will likely ever be. The world is approaching what the late Hans Rosling called “the age of peak child”.



The blue line shows the total world population – rising life expectancy and falling fertility rates mean that the world population of adults will increase while the number of children is stagnating.

This is an extraordinary moment in global history. In the past, child mortality was extremely high, and only two children per woman reached adulthood – if more had survived the population size would have not been stable. This also means that the extended family with many children, which we often associate with the past, was only a reality for a glimpse in time. Only a few generations during the population boom lived in families with many children – before and after two children are the norm. The future will resemble our past, except that children are not dying, but are never born in the first place.

Between 1950 and today it was mostly a widening of the entire pyramid that was responsible for the increase of the world population. What is responsible for the increase of the world population from now on is not a widening of the base, but a fill-up of the population above the base. Not children will be added to the world population, but people in working age and old age. At a country level “peak child” is followed by a time in which the country benefits from a “demographic dividend”. The demographic structure of a country is reshaped so that the proportion of people of working age rises and that of the dependent young generation falls. The demographic dividend can result in a rise in productive contributions and a growing economy.1 Now there is reason to expect that the world as a whole benefit from a “demographic dividend”.

The big demographic transition that the world entered more than a century ago is coming to an end: Global population growth peaked half a century ago, the number of babies is reaching its peak, and the age profile of the women in the world is changing so that ‘population momentum’ is slowly losing its momentum. This is not to say that feeding and supporting a still rising world population will be easy, but we are certainly on the way to a new balance where it’s not high mortality keeping population growth in check, but low fertility rates.