We ask why, in many circumstances and many environments, decision-makers choose to act on a time-regular basis (e.g. adjust every six weeks) or on a stateregular basis (e.g. set prices ending in a 9), even though such an approach appears suboptimal. The paper attributes regular behaviour to...

This paper documents patterns of price setting at the retail level in the euro area, summarized in six stylized facts. First, the average euro area monthly frequency of price adjustment is 15 p.c., compared to about 25 p.c. in the US. Second, the frequency of price changes is characterized by...