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Hi All,

I am a new BI developer, and I currently developing a report with a requirement to calculate the number of orders packed in the last hour and show this measure in a stacked column chart by packers.

 I used the DAX code below 

Orders Packed last hour =

var _AnHourAgo =

MAX(Fact_PPDOrderTransitionLog[PackedOnDate]) - TIME(1,0,0)

var _LastHour =

FILTER(Fact_PPDOrderTransitionLog, Fact_PPDOrderTransitionLog[PackedOnDate] >= _AnHourAgo)

var _LastHourSum =

    SUMX(_LastHour, [Number Of Orders Packed])

return

    _LastHourSum

The results are accurate when placed in a card visual. However, when used in stacked column chart I get unexpected results as can be seen.

Please can anyone help with a solution on how to fix this issue as this will really help me out.

pictures of the data set is shown below 

 The important columns are the PackedOnDate, and updatedbydesignation (as packers) , I also have a date table if that helps. 
Thanks, any help is very welcome