Qlik sense: Filtering on a calculated dimension

[mazried1]

Please guide me!

Im looking for solution, how to filter top 5 brands from dimension, based on variance (ACT-PY), and to have ACT in measure?

Dimensions:

1.Business unit

2. Brand - > ! Issue here - how to filter TOP 5 brands  based on var. ACT-PY

Measure:

ACT

Many thanks!