The incentive characteristics of a so-called “mixed” system were first studied in the context of payment by the supplier (Ellis and McGuire, 1986)7 and were generalized by Newhouse (1996) and applied to plan payments. The prospective component, x ̄ from above, can be adjusted to risk. Box 4.3 describes the proportional risk-sharing modality currently used in Belgium. The content of these theoretical contributions is broadly as follows: (1) Labour market agreements have a significant impact on the volatility of profits and shareholders` income. (2) In contexts where shareholders have a limited ability to cover this additional income risk, the consequences on the equilibrium pricing of financial claims are profound and generally point in the direction of improving the capabilities of the models while reproducing the stylized facts of the economic cycle and financial markets. . . .