The rates of ecosystem degradation and biodiversity loss are alarming and current conservation efforts are not sufficient to stop them. The need for new tools is urgent. One approach is biodiversity offsetting: a developer causing habitat degradation provides an improvement in biodiversity so that the lost ecological value is compensated for. Accurate and ecologically meaningful measurement of losses and estimation of gains are essential in reaching the no net loss goal or any other desired outcome of biodiversity offsetting. The chosen calculation method strongly influences biodiversity outcomes. We compare a multiplicative method, which is based on a habitat condition index developed for measuring the state of ecosystems in Finland to two alternative approaches for building a calculation method: an additive function and a simpler matrix tool. We examine the different logic of each method by comparing the resulting trade ratios and examine the costs of offsetting for developers, which allows us to compare the cost-effectiveness of different types of offsets. The results show that the outcomes of the calculation methods differ in many aspects. The matrix approach is not able to consider small changes in the ecological state. The additive method gives always higher biodiversity values compared to the multiplicative method. The multiplicative method tends to require larger trade ratios than the additive method when trade ratios are larger than one. Using scoring intervals instead of using continuous components may increase the difference between the methods. In addition, the calculation methods have differences in dealing with the issue of substitutability.

生态系统退化和生物多样性丧失的速度令人担忧，目前的保护工作不足以阻止它们。迫切需要新工具。一种方法是生物多样性补偿：导致栖息地退化的开发商可以改善生物多样性，从而补偿失去的生态价值。准确和具有生态意义的损失测量和收益估计对于实现无净损失目标或生物多样性补偿的任何其他预期结果至关重要。所选择的计算方法强烈影响生物多样性结果。我们将基于为测量芬兰生态系统状况而开发的栖息地条件指数的乘法方法与用于构建计算方法的两种替代方法进行比较：加法函数和更简单的矩阵工具。我们通过比较产生的交易比率来检查每种方法的不同逻辑，并检查开发人员的抵消成本，这使我们能够比较不同类型抵消的成本效益。结果表明，计算方法的结果在许多方面有所不同。矩阵方法不能考虑生态状态的微小变化。与乘法方法相比，加法方法始终提供更高的生物多样性值。当贸易比率大于 1 时，乘法方法往往需要比加法方法更大的贸易比率。使用评分间隔而不是使用连续分量可能会增加方法之间的差异。此外，计算方法在处理可替代性问题上也存在差异。