Wierd measure calcualtion when exporting data

This is my measure:

FTE Norm Timeloen = AVERAGEX (
    VALUES ( DimDato[MånedÅr] ),
    CALCULATE([Arbejds-timer i perioden] / 162.5 , FILTER(DimJob, DimJob[Ansættelsesform] = "Timelønnede"))
    )

It works nicely for month in a year and also when I show for Year total:

december as an example works fine, so when I see the result 21.276 it adds up for the data when I extract to excel. When I show year only it gives me:

 

The 23.878 i currectly an average of hours 46561.6 for the year divided by 162.5

But here is the odd thing. When I extract the data. the FTE is higher:

When I add the FTE together it adds up to 38.65

Hos is that when the month is correct, the average FTE over year is correct, but the FTE when added is higher. What am I missing or is the measure not correct?