Due to cyclical oscillations in the economy, a fiscal deficit in a period of time, or in a few subsequent periods of time, does not need to be considered as a sign of long-term unsustainability of fiscal policy if there is a probability that a period of surplus will follow after that. Therefore, as a rule, rather than meeting the budgetary constraint in a certain period of time, the meeting of intertemporal budgetary constraint is considered more important, which requires balancing of the total realized deficits and surpluses in a longer period.