Describe the basic criterion used for comparing a developed country with an underdeveloped one

The average or per capita income is the main criterion for comparing a developed country with an underdeveloped one. Countries with per capita income of Rs 4,53,000 per annum and above in 2004 are called high-income countries, and countries with per capita income of Rs 37,000 or less are called low-income countries. In 2004, India was considered a low-income country because its per capita income was just Rs 28,000. In 2006, the World Development Report to classify countries was based on the average income criterion.