摘要：One of the key features of unemployment rate is its persistence, normally described as hysteresis. This note applies
fractional integration techniques to show that Spanish unemployment is highly persistent and exhibits asymmetric
behaviour, specifically its degree of persistence is higher during recessions (when unemployment is going up)
compared to expansions (when it is going down). Further work should investigate whether this is a stylised fact also in
other countries exhibiting hysteresis.
