In university I learned that adding zero does matter sometimes. However I did not expect to see this in Web Intelligence.

The fact is that the following two expressions are not the equal:

=(Average([Revenue])) In ([Year])

=(Average([Revenue])+0) In ([Year])

The query:

The result:

So the expression (Average([Revenue])+0) In ([Year]) is not equal to (Average([Revenue])) In ([Year]).  But it is equal to: Average([Revenue] In ([Year];[Quarter];[Month])) In ([Year]).

The funny thing this that this is a normal behavior, and there is explanation for this (provided by SAP):

The output context of the aggregation is [Year] in both cases, however the input context of the aggregation is different. In first expression the input is Body ([Year], [Quarter]), however in the second expression the input is the detail context of the [Year], [Quarter] and [Month].