This paper follows a stream of literature on the empirics of sectoral growth rates, originated by Castaldi and Dosi (Income levels and income growth. Some new cross-country evidence and some interpretative puzzles. Our aim is to discuss the statistical properties of growth rates in light of a 'mushroom vision' of growth. In our analysis, we focus on the growth of value added in NACE five-digit sectors in France, Germany, Italy and the United Kingdom between 1995 and 2003. We find that the volatility of sectoral growth rates is negatively correlated with sectoral size, according to a power law, but with steeper slopes than for firms and We wish to thank Giovanni Dosi, Angelo Secchi, Edwin Stuivenwold and Grid Thoma for helpful discussions, and participants of the 11 th International Schumpeter Society Conference in Sophia Antipolis (France) for useful comments. The paper was improved thanks to comments by the editor, Uwe Cantner, and by an anonymous referee. We kindly acknowledge support from the EU funded project DIME. Sandro Sapio also acknowledges support from the EU funded project CO3. All errors remain our own. U.S. sectors. Rescaled sectoral growth rates are well-described by a Laplace distribution in most years. The outcomes of this statistical analysis provide a further empirical foundation to a view of sectoral growth, wherein interfirm correlations, market concentration, and inter-sectoral feedbacks play a major role.