GDP, GNP and a fragile corporate tax base
A small open economy reports GDP of €500 billion and GNP of €440 billion. Net factor income outflows are therefore €60 billion, mostly profits of foreign-owned multinationals. Consumption is €260 billion, investment €100 billion, government spending €90 billion, exports €210 billion and imports €160 billion. The government claims a 'strong recovery' because real GDP grew 5.2% last year, but GNP grew only 1.1%. Unemployment is 6.0%, inflation is 4.0%, and corporation tax from ten firms accounts for 40% of total tax revenue. An opposition economist warns that the economy is 'running hot' and that the tax base is fragile. The finance ministry must prepare a budget update and choose whether to use GDP or GNP as its main planning measure. The multiplier is estimated at 2.0.
1. Calculate net exports and the current account balance if net factor income is the only other item. Explain why GDP and GNP diverge and which measure better reflects residents' living standards.
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Net exports = exports − imports = €210bn − €160bn = €50bn.
Check GDP: C + I + G + (X − M) = 260 + 100 + 90 + 50 = €500bn, which matches the reported GDP.
Current account balance = net exports + net factor income = €50bn + (−€60bn) = −€10bn. The economy has a small current account deficit once repatriated multinational profits are included, even though the trade balance is in surplus.
GDP measures output produced inside the country, regardless of who owns the factors. GNP measures income earned by residents. The €60bn gap is net factor income paid abroad, mainly profits of foreign-owned firms. For living standards of residents, GNP is more relevant because it captures income available to domestic households and government. GDP overstates the resources actually retained in the country when a large share of profits is repatriated. However, GDP is still relevant for production, employment and some tax bases, because multinational activity occurs in the country and pays wages and corporation tax there.
2. Using a multiplier of 2.0, calculate the effect of a €4 billion increase in government spending on GDP. Explain two reasons why the actual effect may be smaller.
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The simple multiplier effect is: change in GDP = multiplier × change in injection = 2.0 × €4bn = €8bn.
The reasoning is that the €4bn becomes income for construction workers, suppliers and employees, who spend part of it; that spending becomes further income, and so on. With a multiplier of 2.0, each €1 of injection eventually creates €2 of GDP.
The actual effect may be smaller for several reasons. First, imports leak out of the circular flow: a substantial share of the spending may be on imported machinery or materials, so the domestic multiplier is lower. Second, crowding out may occur if the economy is near capacity: government borrowing or spending can raise interest rates or compete for scarce labour, reducing private investment. Third, the economy may already be 'running hot' with 4% inflation, so extra demand raises prices more than real output. Supply bottlenecks and low unemployment can also limit the expansion. A judgement should therefore treat €8bn as an upper bound, not a forecast.
3. Evaluate whether the finance ministry should use GDP or GNP as its main planning measure, referring to the tax base, multinational profits and living standards.
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GDP is the better measure of production and the corporation tax base: the multinationals produce in the country, employ people and pay tax there. But GDP is a poor guide to residents' disposable income when €60bn of profits is repatriated. GNP is closer to the income available to residents and is therefore better for planning public services, welfare and living standards.
The tax base is fragile because ten firms provide 40% of corporation tax. A planning framework based only on GDP could overestimate sustainable revenue if those firms relocate, change transfer pricing or face a global minimum tax. The ministry should use GNP or modified national income for living standards, and stress-test the budget against a fall in multinational profits. It should also look at employment, household consumption and the current account, not one headline. A sensible judgement is to use GDP for production and tax monitoring, GNP for income planning, and a clear contingency reserve for the concentration risk.