European Union countries are required by the EU Treaty to keep their budget deficits within 3 percent of GDP, and their public debt within 60 percent of GDP. A new framework to enforce these rules is based on country-specific debt sustainability analyses (DSA) and uses a single indicator, a measure of public expenditure, as the annual fiscal policy target. These changes are welcome. To assess the sustainability of public finances, it is much better to focus on the likely evolution of the debt path than to rely on simple numerical rules.  [….]