Calculation

[kjani]

year	lineitem	value
2019	volume	10
2021	volume	20
2019	gross profit	50
2021	gross profit	80
I have a calculated measure for gross profit rate (gross profit divided by volume)
I want to subtract gross profit rate of year 2021 minus year 2019
And then multiply this difference times 2019 volume.
How do I do that? Please help. Thank you.

[jdbuchanan71]

@kjani Are your Volume is done in a measure it would be along these lines: 

Rate Impact =
VAR _2019GPRate = CALCULATE ( [Gross Profit Rate], YourTable[Year] = 2019 )
VAR _2021GPRate = CALCULATE ( [Gross Profit Rate], YourTable[Year] = 2021 )
VAR _RateChange = _2021GPRate - _2019GPRate
VAR _2019Volume = CALCULATE ( [Volume], YourTable[Year] = 2019 )
RETURN
_2019Volume * _RateChange