Following financial deregulation and the floating of the dollar, both the current account deficit and net foreign obligations (debt and equity) grew rapidly, reaching about 5 per cent of GDP and 50 per cent of GDP respectively by 1990. Since then the current account deficit has fluctuated and net foreign obligations have risen slowly to around 54 per cent of GDP, the great majority of which is debt. By contrast, in 1980, two-thirds of foreign obligations were equity (Parliamentary Library Research Paper No. 3, 2002รถ03, Australia’s Foreign Debt).
It is straightforward to compute that if nominal GDP is growing at 6 per cent per year and if nominal foreign debt grows by an amount equal to the current account deficit, debt will remain stable at 50 per cent of GDP if the current account deficit is equal to 3 per cent (=0.50*0.06) of GDP. Since Australia’s current account deficit has generally been greater than this, it seems likely that debt will grow over time.