(41)The cost of capital should be decreased compared to the level set at the time of adoption of Directive 2009/138/EC and the delegated acts adopted pursuant to that Directive, while maintaining a sufficient level of prudence and protection of policy holders. In addition, the calculation of the risk margin should account for the time dependency of risks and reduce the amount of the risk margin in particular for long-term liabilities, thereby reducing the sensitivity of the risk margin to interest rate changes. Therefore, an exponential and time-dependent element should be introduced.