Measure shows different result than count of column

[Anonymous]

Hi,

I am trying to create a card displaying the total booking threads. I tried two ways to do so:

1) I dropped the column BookingThreadOid on the field section and selected Count of BookingThreadOid.

2) I created a measure computed by CALCULATE(COUNT(bookingdetails[BookingThreadOid])) and dropped it on the field section.

I expected the same result for both ways - however, the numbers largely differ from each other.

Do you have any hint what could be the reason for that?

Thanks and best

[HotChilli]

They are not the same measure.

One is   COUNT(....)

the other is 

CALCULATE(COUNT(...)