Let me emphasize again that's not really a comprehensive
measure of economic development.
We want to know whether people are healthy or not.
We want to know levels of education.
We want to know other indicators of well-being.
But as a shorthand, when I want to get a sense
of a country's overall level of economic development,
I start by looking at the gross domestic product per person,
because that's going to be a pretty good indicator of where things stand.
And indeed, that's what the keeper of the accounts, which is the World Bank, does.
The World Bank keeps very systematic tabulations
on gross domestic product per person, and
it classifies countries in a way that is also extremely helpful for us.
The World Bank gives three categories of countries.
High income countries, middle income countries, and low income countries.
And it puts each nation into one of those three bins,
depending on its measured gross domestic product per person.
Roughly speaking, a low income country is a country where
the domestic production per person is at a level
below a threshold of about $1,000 per person per year.
In other words, roughly $3 per day.
And a middle income country is a country is in a band
between $1,000, roughly, per person and
about $12,000 per person per year.
And the high income countries are countries that are above
the $12,000 per person threshold.
There are then refinements.
The middle income group, which is quite a big one,
is divided between the upper middle income and the lower middle income,
with a dividing line of about $4,000 per person, per year.
In the World Bank, categories provide us with a useful depiction,
a good map of the world, and if you look at the map in front of you,
you can see that those few areas that are shaded blue are the high income countries.
The U.S. and Canada, Western Europe, Japan and Korea,
Australia and New Zealand, and a few other parts of the world.
Add up the population of that high income group, and you find that it's
about 1 billion of the roughly 7 billion people on the planet.
So it's about one in seven in the world, roughly 15% of
the world's population, living in high income countries.
Then take a look at this large middle group
of beige colors.
And you'll see that covers a wide expanse of the world.
And indeed, five out of seven in the world's population, roughly 5 billion
of the 7 billion people on the planet, are in the middle income category.
So that's a big middle.
And that's divided between an upper part and a lower part, roughly half and half.
Approximately 2.5 billion people in the upper middle income category,
and about 2.5 billion people in the lower middle income.
Then look at the countries shaded red.
Those are the poor countries.
The low income category.
And by simple arithmetic, we can say that 7 billion minus the 1 in the high income,
minus the 5 in the middle income, that leaves about 1 billion people,
approximately, living in the low income countries.
We've already noted that the low income countries are heavily concentrated i
tropical Africa and in south Asia,
with a scattering of low-income countries in other parts of the world.
But in our world today,
the poorest countries in the world are concentrated in these two regions.
And most of the world's poor people, therefore,
live in those regions where the countries are in the low income category.
Now, let me mention one more category.
It's not a World Bank category, it's a United Nations category, but
also very important for us to remember.
Even within the low income countries, there are distinctions.
There is a subgroup within the low-income countries
that's in pretty desperate shape.
Not only are they poor, but the human conditions of disease,
of education levels, of social instability, are very bad.
And moreover, this subset of countries is highly vulnerable to droughts,
to floods, to conflict, to violence.