"The economic collapse in the wake of the global financial crises (GFC) and the weaker-than-expected recovery in many countries have led to questions about the impact of severe downturns on economic potential. Indeed, for several major economies, the level of output is nowhere near returning to pre-crisis trend (figure 1). Such developments have resulted in repeated downward revisions to estimates of potential output by private- and public-sector forecasters. In addition, this disappointment in post-recession growth has contributed to concerns that the U.S. economy, among others, is entering an era of secular stagnation. However, the historical experience of advanced economies around recessions indicates that the current experience is less unusual than one might think. First, output typically does not return to pre-crisis trend following recessions, especially deep ones. Second, in response, forecasters repeatedly revise down measures of trend."