In economics, saving-investment balance or I-S balance is a balance of national savings and national investment, which is equal to current account. This relationship is obtained from the national income identity.
Description edit
This is the national income identity:[1]
where
- Y: GDP,
- C: national consumption,
- I: national investment,
- G: government spending,
- EX: export,
- IM: import,
- EX－IM: current account.
The national income identity can be rewritten as following:[2]
where T is defined as tax. (Y-T-C) is savings of private sector and (T-G) is savings of government. Here, we define S as National savings (= savings of private sector + savings of government) and rewrite the identity as following:
This identity implies that the difference of national savings and national investment is equal to current account.[2][3][4]
See also edit
References edit
- ^ Christiano, 2003, Rough Notes on National Income Accounting and the Balance of Payments, Northwestern University, p.1.
- ^ a b Christiano, 2003, Rough Notes on National Income Accounting and the Balance of Payments, Northwestern University, p.3.
- ^ IMF publishment, 2006, Do Current Account Deficits Matter?, accessed 3 February 2015.
- ^ Tejvan Pettinger, 2012, Current Account = Savings – Investment, EconomicsHelp.org, accessed 3 February 2015.