Risk-sharing shall allow asymmetric shocks smoothing into a monetary union. Three adjustment channels could play: public transfers, credits, financial incomes between regions/countries. The literature underlines the actual weakness of this mechanism in Europe whereas it tends generally to suggest that it plays a major role in United-States. In this work, we show for the United-States that financial channel is overestimated. The lack of appropriate data conduces to attribute a too big smoothing part to the risk-sharing instead of Optimum Currency Area effects. Finally, we produce the estimations on euro area where data are much precise and showing that financial channel is more small as predict. These results induce a reappraisal of federal budget. JEL classification: E61, F15, F36.