Bundesbank President Jens Weidmann has called on the euro-area countries to embrace fiscal prudence, arguing in a speech in Hamburg that the tighter the fiscal space, the more central banks will come under political pressure to stabilise economic activity in the short run – even if that does mean compromising on price stability.

The productivity of many firms evolves over time. This impacts on the optimal inflation rate – the rate of price increase with the least distortionary effect on relative goods prices. Our estimates for the United States suggest that, due to firm-level productivity changes, the optimal inflation rate has dropped from somewhat over 2% in the mid-1980s to a current level of roughly 1%.