The world’s population is now estimated to be 7 billion. That’s a big number, but with slowing growth rates (and negative population growth in several developed countries) the most headline grabbing stories of rapid overpopulation are nothing more than echoes of the same stories of the last few thousand years.

Some of the stories around in the news did prompt me to take a look at the South African population pyramids as estimated by Stats SA. Now these figures are extrapolations based on demographic models and the results of the 2001 national census.

As an actuary interested in economic policy I was disappointed with myself that I was surprised by the shape of these pyramids. Some striking messages to say the least.

The overall population pyramid is relatively typical of developing countries with a significant portion of the population under 15 and a significant majority under 35. The growth rate is clearly already slowing, but a surge of youth, many to poor families with limited prospects for good education is still working its way through our population ranks.

An delegate attending a recent CFA Travelling Conference was muttering something about “the problem with South Africa is that different groups have different growth rates and this causes a problem because some groups already have high unemployment so where will the jobs come from?” Newsflash everyone – more people equates to more consumers as well as more workers. The problem is one of public education that ensures even children born to poor families have great education and gain the skills to be productive. High growth rates make the challenge of ramping up public education to the right level and scale required more difficult, but this is an education issue primarily not a population growth issue.

I’m including the “black population pyramid” just for completeness.  Given the massive proportion of the population that is black/african, it looks pretty much the same as the overall population pyramid. What is highlighted here, although is also apparent in the total population pyramid, is the sharp decline from the 30-34 band to the 35-39 band. Now, unless there was a sudden spurt of fertility or a sudden decline in infant mortality 40 years ago, this almost certainly reflects HIV/AIDS deaths. Seeing it here as that sharp decline in our most economically productive age group is quite horrifying.

The indian/asian pyramid is already in the shrinking stage. As higher incomes and education give rise to lower birth rates, the population shrinks in textbook fashion.

The white population pyramid is a mix of standard-shrinking (similar to Indian/Asian) and a shocking emigration-bite / brain drain in the 25 to 40 year age bracket. I feel confident saying this is emigration not HIV/AIDS deaths given the low HIV prevalence in the white population.

These emigrated people will generally be the educated, productive, skilled workers (educated with large state subsidies much of the time) and is a big part of the sluggish economic growth in South Africa.

The size and impact of that brain drain has never been as apparent to me as this population pyramid shows.