Eurozone crisis/Tutorials

Departures from optimum currency area criteria

Currency area theory is concerned with extent to which efficiency gains from currency area membership are offset by losses due to increased vulnerability to external economic shocks, and the term "optimum currency area" (OCA) denotes an area in which such offsets are absent. Although an idealistic concept, it has practical implications because the increased costs of recessions, brought about by increased vulnerability to shocks, can be large compared with the benefits of the efficiency gains. For that reason it is generally accepted that a currency area may not succeed unless it goes a substantial way toward meeting OCA criteria. A currency area fully meets OCA criteria if there is complete price flexibility, or complete cross-boarder mobility of labour and capital. An alternative requirement arises from the fact that increased vulnerability to shocks need not occur if every shock has the same impact on all the economies of the member states. The term "convergence" is sometimes used to denote a condition in which the economies of members states are so similar as to eliminate asymmetric shocks - or to denote an approach to that condition.

The eurozone has not satisfied the OCA labour migration or price flexibility conditions. Labour mobility is low and there is only limited wage and price flexibility. Nor has it satisfied the convergence condition. There has been less price convergence among eurozone countries than among European Union countries as a whole,, and there have been large divergences of productivity, unit labour costs, and current account balances. The progress toward convergence as a result of membership, that was expected by the early proponents of monetary union, has not occurred.

The debt trap

If the annual interest payable on a government's debt were to continue to rise faster than the national income, it would eventually exceed the feasible revenue from taxation. The process is normally hastened by the fact that government debt is traded in a well-informed market. Operators in that market would be aware of the approach of the point at which the government would be forced to default on its debt, and they would be increasingly reluctant to allow that government to continue to roll over its debt. The government concerned could seek to overcome that reluctance by offering them higher interest on future loans, but an increase in the interest to be paid would hasten the process and increase the reluctance of further potential investors. That is what is known as the debt trap, the price formulation of which is the the debt trap identity.

The debt trap could be escaped:

- (i) by repudiation of the debt;

- (ii) (temporarily) by a negotiation with creditors to ease the terms of repayment (termed restructuring);

- (iii) (temporarily) by getting the country's central bank to purchase the debt; or,

- (iv) by a programme of reductions in public expenditure and/or increases in rates of taxation.

Options (i) and (ii) have the drawback of making future investors reluctant to buy the government's bonds. Option (iii) can also have that effect if it causes an inflation that reduces the value of the currency in which the debt is to be repaid. Option (iv) is free from that drawback, but is effective only if it avoids creating a recession that increases the deficit (by the operation of the country's automatic stabilisers).

Fewer options are available to members of a currency union, however. Option (iii) may be excluded by the fact that monetary policy is no longer under the control of the borrowing government. That fact also prevents the use of monetary policy to counter the recessionary consequences of (iv), (without which that option may be ineffective); and the rules of the currency union prevent the exchange rate deprecation that might otherwise counter them. To make (iii) possible and (iv) easier, a further option would be (v) - to leave the currency union.