National Income is the total money value of all services and goods produced within a country and the income from abroad for a given period, usually a year.
GDP, GNP, and GNI determine the national income.
National Income formula = C + G + I + X + F – D
Where,
C = Consumption
G = Government expenditure
I = Investments
X = Net exports (exports - imports)
F = Foreign production by national residents
D = Domestic production by non-national residents
GNI measures income generated by the country's citizens, regardless of the geographic location of the income.