Substract 2 measures when only when one is not blank, else return blank or 0

[BobKoenen]

I have a matrix in which I have 2 measures and now I want to create a 3rd measure which gives me [measure1 - measure 2] only when measure 2 is not blank. If measure 2 is blank then measure 3 should also be blank.

Outcome

Department	employee	Measure 1	Measure 2	Measure 3
IT	John	10
IT	Ilse	20	50	-30
Finance	Jack	24	10	14
Finance	Josie	34	30	4
Finance	Jebaca	65
HR	Jay	65	50	15
HR	Jones	50

I have tried the measure below but is does not work unfortunatly. 

Measure 3 =

VAR BB = [Measure 1]

VAR VC = [measure 2]

RETURN

IF (

NOT ISBLANK ( BB ),

BB - VC,BLANK()

)

I hope you can help me

[AlB · Accepted solution]

Hi @BobKoenen 

Measure 3 =
VAR BB = [Measure 1]
VAR VC = [measure 2]

RETURN
IF (
NOT ISBLANK ( VC ),
BB - VC,BLANK()
)

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