The word ‘macro’ derived from Greek word ‘Makros’ which means large . So the term macro denotes big or large . Macroeconomics deals with the functioning of the economy as a whole . It studies the aggregate form of an economy . So , it is also known as income theory as it studies national income ,national output general price level , level of employment , saving and investment .
According to Edwin Mansfield ,”Macro economics deals with behavior of economic aggregate such as national product and level pf employment “. In the word of K.E Boulding ,”Macro economics deals not with individual quantities but with aggregate of these quantities not with individual income but with national income not with individual prices.
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But with national price level , not with individual output but with national output “. Therefore macroeconomics explains the aggregate economics variables such as aggregate demand ,aggregate supply national income .National output inflation deflation unemployment , business cycle etc.