Le taux de chômage d'équilibre, anciennes et nouvelles approches

Abstract

In each country, there exists an equilibrium rate of unemployment, determined by wage bargaining features and labour market functioning, below which the rate of inflation accelerates. Two alternative approaches have been developed to define and to evaluate this equilibrium rate. According to the Phillips curve, which is based on empirical and macroeconomic works, the Non Accelerating Inflation Rate of Unemployment only depends on the trend of labour productivity. The NAIRU is relatively steady ; economie policy cannot make it decrease. The lower trend of labour productivity explains a significant part of the increase in European equilibrium rates of unemployment ; however, the latter are currently undoubtedly below effective rates of unemployment. According to the « new unemployment theories », which are based on theoretical and microeconomic works, the equilibrium rate of unemployment is determined by the intersection of Wage-Setting and Price-Setting curves, and is influenced by ail the variables which play a part in wages and priees formation (social contributions rates, real interest rates, minimum wage, trade unions power, unemployment benefits, terms of trade, etc.). The equilibrium rate of unemployment is then influenced by economie policy and may fluctuate. The effective unemployment rate is always close to the equilibrium one. However, the existence and the features of the real wage target that are postulated by this approach, set many theoretical and empirical problems. Considering both the results of previous empirical works and those of our own estimations, the robustness of the « new approach » is not set up. The traditional approach of the Phillips curve is still relevant.