A world of 4 income levels

I grew up with the idea that there are developed countries and developing countries, the “rich” world and the “poor” world. I didn’t actively consider this teaching. It’s just always been there. And it’s wrong.

In his excellent book Factfulness, Hans Rosling shows that wealthier countries tend to have smaller families and a low child mortality rate. In contrast, poorer countries are more likely to have larger families and a high child mortality rate.

Plotting the spread of countries in the 1960s gives a reasonable approximation of a cluster of “developed” countries with small families where most children survive and a cluster of “developing” countries with larger families where more children die. But that was in the ’60s.

The world has changed a lot since then, and that model of dividing the world into two buckets no longer fits the data. Most people in the world are somewhere in the middle.

And more helpful than dismantling a worldview is providing a new model to replace it: a model with four income levels instead of two. The numbers reflect most people’s reality, with most of us somewhere in the middle.