The euro zone's business climate includes asymmetric shocks and business cycle deviations that cloud the reading of the common economy. The model presented here takes explicit account of this constraint. It coher-ently and simultaneously produces a composite indicator of the common economy and a set of business cycle deviation indicators for the leading euro zone countries. This model hence offers a retrospective reading grid of the European cycle over the last twenty years, from the second oil shock to the U.S. slowdown in 2001. When added to the common economy of the euro zone, considered to be a fully-fledged economic entity, the diagnosis is enhanced by the analysis of the specific national business cycles. The business cycle deviation indicators hence clearly illustrate the more laborious nature of disinflation in the «Latin» countries in the 1980s and then the conflicts of interest and divergences that accompanied the EMS crises in the 1990s. The reading of these real-time indicators provides an understanding of the recent relative cyclical positions of the countries in the euro zone.