Indeed, without using the placeholder, 4005 is the fixed parameter ID of all aggregation parameters (it's the table column that holds the value in the hidden aggregator element).

As the docs say:

• Without using a placeholder: Set the value to the DMA ID/element ID of the hidden Skyline Generic Aggregator element, followed by a colon and the relevant aggregation index. You can find the relevant DMA ID/element ID by looking in the Element.xml file for this hidden element in the Elements folder on the DMA. You can find the index by going to the aggregation page of a view, selecting the aggregation rule, and then checking the Index column in the table tab.

This means you will need to look up the DMA and element ID of the hidden aggregator element in the Element.xml file in C:\Skyline DataMiner\Elements\Skyline Generic Aggregator. Let's say the DMA ID is 1 and the element ID is 2, your content of your shape data will be:

1/2:4005:aggregationIndex

Aggregation index is <GUID of the rule>.<View ID>.-1 (most of the time).

In the end it's much easier to use the "aggregationRule" placeholder 😉

If this is for testing purposes, you could also use that placeholder in shape text, see what the output is and that will actually be the content you should put in your Aggregation shape data.