Besides size of per capita income , what other property of income is important in comparing two or more societies?
Besides the per capita income or the average income of a country, the following are other criterion for the cateogorisation of a country into one that is developed and one that is not:
1.Gross Domestic Produce(GDP)
2. The distribtution of income among the citizens of that particular country
3. Infant mortatilty rate(IMR)
4. Net attendance Ratio
5. The health of the citizens.
All though most are not rwholly related to income, you might want to include the same in your points.
Hope this helps..