Statistical properties of business firms structure and growthK. Matia1, Dongfeng Fu1, S. V. Buldyrev1, F. Pammolli2, M. Riccaboni2 and H. E. Stanley1
1 Center for Polymer Studies and Department of Physics, Boston University Boston, MA 02215 USA
2 Facoltà di Economia, Università di Firenze and CERM Via Banchi di Sotto 55, 53100 Siena Italy
(Received 10 March 2004; accepted in final form 17 May 2004)
We analyze a database comprising quarterly sales of 55624 pharmaceutical products commercialized by 3939 pharmaceutical firms in the period 1992-2001. We study the probability density function (PDF) of growth in firms and product sales and find that the width of the PDF of growth decays with the sales as a power law with exponent . We also find that the average sales of products scales with the firm sales as a power law with exponent . And that the average number products of a firm scales with the firm sales as a power law with exponent . We compare these findings with the predictions of models proposed till date on growth of business firms.
89.90.+n - Other topics in areas of applied and interdisciplinary physics.
05.45.Tp - Time series analysis.
05.40.Fb - Random walks and Levy flights.
© EDP Sciences 2004