One way managers can assess markets is by looking at gross national income or GNI which measures the value of all production in the domestic economy together with the income the country receives from other countries, less similar payments it has made to other countries.
Managers can also look at gross national product or GNP. Conceptually, world GNI and world GNP are the same.
Gross domestic product or GDP allows managers to assess countries in which the output of multinationals represents a significant share of activity.