Day to Day Calculated Column

[vega]

Hello,

I have the following example dataset:

Hotel	Date	Amount
A	1/1/2017	100
A	1/2/2017	200
A	1/3/2017	300
B	1/1/2017	400
B	1/2/2017	500
B	1/3/2017	600
A	1/1/2018	700
A	1/2/2018	800
A	1/3/2018	900
B	1/1/2018	1000
B	1/2/2018	1100
B	1/3/2018	1200

What I'd like is a calculated column that computes the previous years amounts on a day to day level. So, instead of matching the 1/1/2018 to 1/1/2017, we are matching day of the week. So, we want to match 1/1/2018 to 1/2/2017, basically we want to subtract 364 days. So this is what I'm looking for;

Hotel	Date	Amount	DoD
A	1/1/2017	100
A	1/2/2017	200
A	1/3/2017	300
B	1/1/2017	400
B	1/2/2017	500
B	1/3/2017	600
A	1/1/2018	700	200
A	1/2/2018	800	300
A	1/3/2018	900
B	1/1/2018	1000	500
B	1/2/2018	1100	600
B	1/3/2018	1200

 
Does anyone know how to go about doing this?

Thanks!

[ccakjcrx · Accepted solution]

Hey @vega!

I was able to use LOOKUP and specify both 364 days ago, and hotel. I added a calculated column to my test data model using the following expression:

PriorYearHotelValue = 
IF(
    Sheet1[Hotel] = "A",
    LOOKUPVALUE(Sheet1[Value],Sheet1[Date],Sheet1[Date] - 364,Sheet1[Hotel], "A"),
    LOOKUPVALUE(Sheet1[Value],Sheet1[Date],Sheet1[Date] - 364,Sheet1[Hotel], "B")
)

In my test data, I started with three columns: Date, Hotel, & Value. The LOOKUP expression looks for the value in Sheet1[Value], where date matches 364 days ago, and hotel matches A. I only have two hotels, so my IF statement executes the first LOOKUP if matches on A, and the second if not.

Click HERE to access my .pbix file if you need it.

Hope this helps! 

[vega]

Thank you, I appreciate it. I was also able to come up with an alternate solution. I'll leave it here in case it helps anyone else out in the future.

=
VAR previousDate = 'Legacy Trans'[Date]-364
RETURN
CALCULATE(
	SUM('Legacy Trans'[Amount]),
	ALLEXCEPT('Legacy Trans','Legacy Trans'[Hotel]),
	'Legacy Trans'[Dates] = previousDate
)