GDP of 20,000 less consumption of 13,600 and government purchases of 3,600 leaves national saving of 2,800
National saving is the part of an economy’s income that is not consumed by households or used up by government purchases in the period: S = Y − C − G. In the worked economy ($ billions), that is 20,000 − 13,600 − 3,600 = 2,800, or 14% of GDP.
S = Y − C − G
It is saving in the national-accounts sense — output available to add to the stock of capital, at home or abroad — and it has nothing to do with the balances in savings accounts. Money moving from a current account to a deposit account does not change it at all.
Worked example
Y = 20,000, C = 13,600, G = 3,600
S = 20,000 − 13,600 − 3,600
S = 2,800
(14% of GDP)
Private saving of 3,400 and public saving of −600 add to the same 2,800
Add and subtract net taxes T and national saving splits in two: S = (Y − T − C) + (T − G). The first bracket is private saving — what households and firms keep from their after-tax income — and the second is public saving, the government’s budget balance. With net taxes of 3,000, private saving is 20,000 − 3,000 − 13,600 = 3,400 and public saving is 3,000 − 3,600 = −600, a deficit.
S = (Y − T − C) + (T − G) = Sp + Sg
The split matters because the two parts respond to different things. Private saving answers to interest rates, income and confidence; public saving answers to tax and spending decisions and to the business cycle. A deficit is negative public saving, and it subtracts from what households save.
The split
Sp = 20,000 − 3,000 − 13,600 = 3,400
Sg = 3,000 − 3,600 = −600
S = 3,400 + (−600) = 2,800
Investment of 3,300 against saving of 2,800 means 500 borrowed from abroad
In a closed economy national saving must equal investment: output not consumed by households or government is, by definition, invested. In an open economy the equation gains a term: S = I + NCO, where net capital outflow is the saving a country lends abroad net of what it borrows. Here S = 2,800 and I = 3,300, so NCO = −500 — the economy invests more than it saves and foreign lenders finance the difference, about 15% of its investment.
S = I + NCO
The same 500 appears in the trade accounts. Net capital outflow always equals net exports, so an economy that borrows 500 from abroad runs a trade deficit of 500: exports of 2,300 against imports of 2,800.
Where saving goes
2,800 = 3,300 + NCO
NCO = −500
(and NX = 2,300 − 2,800 = −500)
Raise government purchases by 400 with nothing else changed and national saving falls by 400
Because public saving is part of national saving, a wider budget deficit lowers national saving one-for-one unless households save more to offset it. In the example, 400 more of government purchases with taxes, consumption and investment unchanged takes public saving from −600 to −1,000 and national saving from 2,800 to 2,400; with investment fixed, net capital outflow and net exports fall by the same 400. The table on this page runs that arithmetic — the “twin deficits” link between the budget and the trade balance.
Robert Barro’s Ricardian-equivalence argument says households who expect future taxes to repay the borrowing will save more today, leaving national saving unchanged. The evidence is that they offset part of a deficit, rarely all of it, which is why deficits and trade deficits have tended to move together in the United States without moving in lockstep.
Decades of investing more than it saves left the US with a net international position of −$21.3 trillion
The United States has run a negative net capital outflow in most years since the early 1980s, financing part of its investment with foreign saving. The accumulated result is its net international investment position: the value of US-owned foreign assets minus foreign-owned US assets. BEA put it at −$21.3 trillion in the first quarter of 2026.
Public dissaving is a large part of the story. The federal deficit was $1.77 trillion in fiscal year 2025, about 5.8% of GDP — negative public saving large enough to absorb a sizable share of what households and firms save.
Net of depreciation, US national saving was negative through 2008–2010 and again in 2020
Published saving comes in two forms. Gross saving counts all income not consumed; net saving subtracts the capital that wore out during the period, depreciation. Net national saving is the addition to the country’s wealth, and it can be close to zero even when gross saving looks healthy.
US net national saving was negative in every quarter from the start of 2008 to mid-2010, in the second quarter of 2020, and briefly again in the second half of 2024, according to BEA’s series. The calculator’s figure is gross or net depending on which consumption and investment figures you enter; keep the two consistent.
This is the economy’s saving, not the return on a National Savings certificate
Search results for “national savings calculator” mix two different things. This page computes national saving in the macroeconomic sense — the S in S = I + NCO. Government savings schemes that carry the same name, such as Pakistan’s National Savings certificates, need a profit calculation instead; the compound interest calculator on this site handles a fixed rate compounded over a term.
Sources & References
Figures on this page are checked against primary, authoritative sources. Links open in a new tab.