 The framework based on counting-up units contrasts with other proposals for general frameworks for biodiversity, including those proposals that have attempted to include a variety of calculations—endemism, dissimilarity, rarity, etc.—within the definition of biodiversity (see below). The framework based on counting-up units implies not only that biodiversity as variety is that total count, but also that we can carry out lots of other important, associated, calculations that will be useful for decision-making and policy—notably looking at gains and losses. This idea of a biodiversity “calculus” contrasts with the ecologically oriented perspective that there are many different indices called “biodiversity”.