The first thing that you need to do is determine the Gross Domestic Product (GDP) or National Income of the area that you wish to calculate the per capita income for. If you want to calculate the per capita income for the population of an entire country, then you can get the value of GDP or National Income for the country from the World Bank website.
Get an estimate of the population in the area by contacting the union office or, in case you are making the calculations for the whole country, the World Bank website. You will obviously be working with an estimate of population, as an accurate figure is nearly impossible to get.
Once you have acquired the value of GDP or National Income and the population estimate for a area, put the values in the formulate “GDP or National Income/total population” to get the per capita income. For example, if the GDP of a country for the year 2012 is 550 million dollars and the total population is 1 million, then the per capita income for this country is “550 million/1 million”, which will amount to 550 dollars. This basically means that every individual in this country earns an average of 550 dollars per annum.