A question that is becoming crucial: What types of public spending (or tax cuts) have a positive impact on potential growth?

Governments increasingly intend to intervene in the real economy. We are not talking about countercyclical stimulation of activity during recessions and crises, but policies for investment in infrastructure, healthcare, energy transition, industry and reshoring, networks, training and innovation, etc. Governments run up debt or raise taxes to finance these new types of spending. In order for this new spending not to jeopardise fiscal solvency and to have a net positive effect on the economy, it must therefore increase potential, long-term growth. The question of the link between public spending and potential growth (and not that of the fiscal multiplier, which is a short-term, cyclical concept) is therefore becoming central: what are the right types of public spending from this point of view? We compare OECD countries, and we seek to determine what types of public spending (and symmetrically what tax cuts) have a positive correlation with productivity gains or the employment rate, and therefore with potential growth. This analysis seems to show that to boost potential growth, it is effective to: Increase public spending on R&D, education and healthcare; Reduce corporate social contributions and production taxes. Other types of government spending or other taxes do not seem to have any impact on productivity gains or the employment rate.