Is the problem in OECD countries primarily on the supply or the demand side?

T his old debate continues among economists, pitting supporters of supply-side policies against supporters of demand-side policies. The stimulus packages being implemented in OECD countries are a compromise: they combine demand stimulus (transfer payments to households, subsidies for companies, improved social welfare) and supply stimulus (investments in infrastructure and the energy transition, support for innovation, education, industry, job creation, etc.). But from a macroeconomic viewpoint, is the problem in OECD countries primarily on the supply or the demand side? We look at the situations of the United States, the United Kingdom, Japan, Germany, France, Italy, Spain and the OECD as a whole: When we look at the savings-investment equilibrium, we see excess savings at present in Japan, Germany, Spain and Italy; When we look at productivity gains, we see a constant slowdown in all countries, which obviously corresponds to a supply problem; When we look at income distribution, we see it has skewed against wage earners, giving rise to a demand problem in the United States , Japan and in the OECD as a whole . Altogether, the problem is primarily: On the demand side in Japan; On the supply side in all the other countries, especially the United Kingdom and France.