What is the advantage of per …

a. Average income /per capita income which is the total income divided by the population.
b. It serves as an important tool of comparing different nations and classifying them as rich countries or low income countries.
c. It gives us an information about what an average person is likely to earn and therefore is an important indicator of development.
d. World bank has specified the criterion for categorising countries into developed, developing and underdeveloped countries.
e. It is based on assumption that in countries with  high per capita income , people would have high standard of living and would be in a position to not only manage their basic necessities  but other things required to lead a  life.
f. This criteria however only takes into account the quantitative aspect and doe not talk of how the income is distributed among the different sections of the society.