The reliability of real-time estimates of the euro area output gap

► We assess the reliability of euro area real-time output gap estimates available from 1999 to 2010. ► Estimates exhibit high parameter instability and model uncertainty, while data revisions are minor. ► Some estimates are less uncertain, but do not appear to be fully reliable along some dimensions. ► Over the same sample, filter-based US estimates are revised to a lesser extent than euro area estimates. ► However, the sign of the level of US estimates tends to be revised more often than for the euro area.