These maps show the changing distribution of Gross Domestic Product (GDP)/capita. Gross Domestic Product is the total money value of goods and services produced in a country in one year. GDP/capita is the total divided by the number of people in the country. In other words, GDP/capita is a measure of the value of products made and services provided by each person. It is a measure of the average productive capacity of people in one country. Since productive capacity has a strong influence on living conditions, including wages, food, housing and healthcare, GDP/capita provides a rough estimate of living standards and is frequently termed 'income'.

These maps show GDP/capita measured at purchasing power parity (PPP). This means that the value of goods in one country is valued in US dollars using the ratio of the cost of a basket of common goods in the two countries. This takes into account general price differences in the two countries.

A separate presentation, in this section of the Atlas, presents changing GNP (Gross National Product)/capita data. GNP differs from GDP through the inclusion of the overseas income of nationals. So, for example, the US GNP includes the overseas income of corporations based in the US. GNP/capita price data is available for a longer period. But GDP (PPP)/capita is a more robust and straightforward measure of comparative levels of economic activity.

What the maps suggest

PPP (purchasing power parity) comparisons of national income take into account differences in living costs among countries. As a general rule, food, housing, transport and other goods, are cheaper in the global south than in the industrialized north. As a consequence, comparisons using national income at purchasing power parity suggest that some aspects of economic inequality are less marked than if the comparison is made with market exchange rates of the currencies concerned.

For example, the maps below show few countries with per capita income less than $1 per day. And, the picture of African per capita output is less bleak than if output were compared using exchange rates (as is done in the GNP/capita series of maps).

This map series suggests some improvement in national output in the global South. Most of Asia and much of Africa have per capita national output below $2 per day in 1975. By 1999, no large countries in Asia, and few in Africa are below that level. Most have shifted to the range $730 to $5000 ($2 to $14 per day).

GDP (PPP) / capita measures of output do not show the striking growth of East Asian miracle economies as strongly as measures of GNP/capita. South Korean output per capita has shifted from the $730 to $5k category to the $10k to 20k category.

The Data

There are several different ways of comparing national output. In this set of maps, GDP/capita is measured at purchasing power parity. This means that national outputs per capita are compared using the equivalent buying power of currencies (rather than market foreign exchange rates). These data come from the World Bank's World Development Indicators 2001.

Data intervals

Less than $1 per day ($365 per person each year) is widely used as a global standard of absolute poverty. (Some problems with the use of GDP/capita as a measure of individual poverty are noted below). The World Bank says this level is the median of the ten lowest national poverty lines (World Bank 2001: Box 1.2). It is used here as a graphic indication of low levels of output or productivity, and one that is increasingly widely used. The World Bank uses $2 per day as a reflection of poverty lines of lower-middle income countries.

The remaining intervals are arbitrary but recognizable cut off points. For comparison, the World Bank used these intervals as its categories in its World Development Report 2000:

Problems of using GDP/capita as a poverty line

GDP/capita is a measure of average national output. There are at least two kinds of problems with this as a measure of individual incomes:

1. Problems of measurement. Non-monetized activities may be poorly estimated (e.g. the products of peasant agriculture) or excluded (e.g. domestic work maintaining the home).
2. Problems of conceptualization. GDP/capita is a simple average of output divided by number of people. So it does not say anything about the distribution of national income between rich and poor.

What we can say is that GDP/capita provides a rough estimate of average national productivity and national productivity sets bounds on average living standards.