Fiscalité, coût d’usage du capital et demande de facteurs : une analyse sur données individuelles

In this paper we analyze the impact on the demand of capital and labour of changes in their relative costs, using micro data. We especially highlight the role of the user cost of capital, for which we propose an original measure based on the cost of debt and the cost of equity. We hence take advantage of changes in the taxation of capital to build instrument variables and to estimate a complete system of factor demands. First we find that the elasticity of substitution between capital and labour is relatively weak in the non manufacturing sector, about 0,4, whereas this parameter range from 0.6 to 0,8 in the manufacturing sector. Secondly, we show that the price elasticity of the demand for goods is quite high, and is almost equal to 2 in both industries. Thirdly and probably the most interesting result, we find a significant and direct relationship between the user cost of capital and the stock of capital, which does not appear in most former studies on French data. In a standard model of factor demand, our results mean that the wealth effect dominates the substitution effect. As a result, lowering the user cost of capital would lead, at partial equilibrium, to increase not only investment but also the employment level and output.