Structures de revenus et propensions différentes à consommer. Vers une équation de consommation des ménages plus robuste en prévision pour la France

In efforts to better understand household consumption behavior, the evolution and structure of household income have received less attention than the evolution and structure of household wealth. Yet, significant shifts in the structure of household income have occurred since the 1980s, particularly favoring old-age pensions and unemployment benefits. Several reasons explain why the composition of household income influences consumption. One reason is the aggregation of behaviors that differ across households with different types of income. A second reason relates to the greater persistence of certain income streams, which are associated with a higher propensity to consume: a positive (or negative) shock stimulating (or affecting) such income results in a larger increase (or decrease) in permanent income compared to non-persistent income sources. This is illustrated within the theoretical framework of the life-cycle model. Econometric estimates based on 1995-base data indicate that the wage bill, social benefits, and the income of sole proprietors play a more critical role than other forms of income. When compared against specifications that prioritize wealth effects—particularly housing wealth—or interest rate effects, the income structure effects highlighted here offer a new, potentially dominant avenue for understanding consumption trends. However, further substantiation of this result through a study using microeconomic data would be desirable; this is left for future research. In particular, the surprisingly high propensity to consume among sole proprietors warrants closer examination. It will also be necessary to test the robustness of these results against the rebasing of the national accounts.