Macroeconomics is a part or branch of the Economía, which aims to study the collective magnitudes corresponding to an economic system. The magnitudes are generally established for a specific country or territory. In macroeconomic terms, National Income is understood as the set of goods and services produced in a national economy within one year. It is usually represented by Y, which, in turn, is identified as the sum of the Gross Domestic Product plus exports.
Understanding by Gross Domestic Product, GDP, the sum of private consumption, C; public spending or consumption, G; investment, both public and private, I; and the difference between exports e imports (XM). Due to its approach, macroeconomics is useful for the political and administrative management of a country. This branch of economics aims to simplify the great variety of economic relations existing in a state, through the use of so-called economic models.
The gross domestic product of a given State can also be defined through the value added. Or, what is the same, as the sum of the net inputs of each sector of the economy. And, finally, it is possible to define it, in terms of income and distribution, as a sum of wages from work, RL; income from capital, RK; financial interests, Rr; the benefits, B; amortizations, A; and the difference between indirect taxes, Ii and subsidies Sb.
All these figures are calculated independently of the number of inhabitants. However, it is called per capita income, precisely, the quotient between the gross domestic product and the number of inhabitants in a given state or national economy. Furthermore, the balance of the balance of trade, requires that saving, A, minus investment, I, be equal to the difference between exports and imports.