# Calculated Measures

This first iteration of Calculated Measures allows Orbit dashboard editors to calculate their own measures to present on visualisations. Being the first release, this version of Calculated Measures comprises of simple operators that allow you to add, subtract, multiply, and divide data variables and/or full counts of system tables together.

There are many benefits of being able to derive results from existing variables but the common case for this entry level calculation capability is ratios. Ratios find proportions such as cost per booking, or average booking per person, so that you can keep tracking key stats that inform whether you are meeting defined KPIs.

If you compare a calculated measure in Orbit with its equivalent calculated in FastStats, then you may see a discrepancy between the two values. This is due to rounding calculation process that occurs in FastStats. The value provided in Orbit is more accurate to a higher level of precision.

To add a calculated measure, and for an explanation on designing calculated measures, see the following guides: