In Sigma, calculations live in the elements they were created in. For example, if you create a calculation in a bar chart element - like SUM([Sales]) - it lives in that bar chart and is accessible only in that element and any child elements. This is why it is important to add calculations to base tables or parent tables if you need to use the calculation in multiple elements. You can use the data source options listed in the question above to better understand where to find and create your calculations.