3.3
The total available savings in an economy is the sum of private savings by households and public savings by the government.
Private savings are the income households have left after paying taxes and covering their consumption expenses. This is expressed as: S equals Y minus T minus C — where S is private saving, Y is total income, T is taxes, and C is consumption.
Public savings, on the other hand, is the difference between what the government collects in taxes and what it spends. This is shown as T – G, (Read as T minus G) where T is tax revenue and G is government spending.
Together, private and public savings form the total savings in an economy. These total savings must match the total investment.
This follows from the closed-economy national income identity, Y=C+I+G.
National saving is what’s left after consumption and government spending, S=Y−C−G.
Substituting for Y gives S=(C+I+G)−C−G=I.
Thus, in a closed economy, total savings equals total investment.
Saving plays a central role in supporting investment and economic growth. In macroeconomics, national saving is composed of two distinct components: p…
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