Before adopting the common currency, countries have to show sufficient and sustainable stability in their monetary and fiscal policies. The two-year minimum period within ERM II ensures that the fixed exchange rate regime is supported by the fundamentals.
In years when fiscal policy has not been used for stabilisation purposes the fiscal impulse, i.e. the contemporaneous contribution to GDP-growth from fiscal policy in a given year, has been close to zero. As is the case in most countries it is also politically easier to increase public expenditure and reduce taxes than the opposite in Denmark.