You can use the compute engine and history periods to create a rolling average for any given metric.
Details of how to do this are shown below:
1) the first thing you need to do is add a cell or headline that will retain the average value. To do this you need to use the 'Dataviews' section under the Advanced section of the sampler.
2) You then need to add a history period over which you want to collect an average. This is added to the rules section of the setup, here is an example:
3) within a rule you can now add a value to the cell you created in the first step using rule syntax like below