Creating a Measure based on Previous day

[nosaj03]

Hello all!

I have a Sales table of employees by day by item category and total time on sale

I want to create a measure that shows the averge time for sales for by employee for the previous day based on current day.

Example

Date	Employee	Group	Item group	Sales	Time
5/19/2020	Joe	Tech	IOS	3	819
5/19/2020	Joe	Tech	Android	11	2247
5/19/2020	Joe	Tech	Windows	31	11056
5/19/2020	Joe	Tech	Gaming	1	176
5/18/2020	Joe	Tech	IOS	4	919
5/18/2020	Joe	Tech	Android	15	254
5/18/2020	Joe	Tech	Windows	26	12001
5/18/2020	Joe	Tech	Gaming	14	201

I want to find out the average time for Joe on 5/18 so the formula is sum(Time)/sum(sales)

I've been using the following formula

Calculate(divide(sum(Time),sum(Sales),0),filter(date = now()-1)) and it returns nothing. 

Other times its gives me the "The expression refers to multiple columns. Multiple columns cannot be converted to a scalar value" or the Divide by Zero error. 

I'm stuck here. Any help would be greatly appreciated.

[Anonymous · Accepted solution]

@nosaj03 

You should use Today() instead of Now(), because Now()-1 return current time-1 second, not previous day.  And for the sample you provided, you can test it by replace Today() with Date(2020,5,19) to check the average of 5/18. 

Measure Calculate(divide(sum([Time ]),sum([Sales]),0),filter('Table',[Date]= TODAY()-1))

Paul Zheng _ Community Support Team
If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

[nosaj03]

@Anonymous Thanks! This worked out perfectly!!!!

[amitchandak]

@nosaj03 , To avoid divide by 0 use divide . which you have done correctly

Calculate(divide(sum(Time),sum(Sales),0),filter(Table,[date] = Today()-1))

This might not work if date is selected then you have to use all
Calculate(divide(sum(Time),sum(Sales),0),filter(all(Table),[date] = Today()-1))

Better to use a date table

Last Day Non Continous = CALCULATE(divide(sum(Time),sum(Sales),0),filter(all('Date'),'Date'[Date] =MAXX(FILTER(all('Date'),'Date'[Date]<max('Date'[Date])),Table['Date'])))
Day behind Sales = CALCULATE(divide(sum(Time),sum(Sales),0),dateadd('Date'[Date],-1,Day))

To get the best of the time intelligence function. Make sure you have a date calendar and it has been marked as the date in model view. Also, join it with the date column of your fact/s. Refer :
https://radacad.com/creating-calendar-table-in-power-bi-using-dax-functions
https://www.archerpoint.com/blog/Posts/creating-date-table-power-bi
https://www.sqlbi.com/articles/creating-a-simple-date-table-in-dax/

See if my webinar on Time Intelligence can help: https://community.powerbi.com/t5/Webinars-and-Video-Gallery/PowerBI-Time-Intelligence-Calendar-WTD-Y...


Appreciate your Kudos.

[nosaj03]

@amitchandak thank you for the insight. I have a date table that I created. 

When I use the formula you provided below 

Day behind Sales = CALCULATE(divide(sum(Time),sum(Sales),0),dateadd('Date'[Date],-1,Day))

It is still giving me the total based on the entire table and not the previous day. 

[amitchandak]

@nosaj03 , can you share the screenshot of the issue. This should have worked. Hope you are using date and any other date-related column from date table

[nosaj03]

@amitchandak using the exact formula you gave me the Avg Time for 5/18 should be 227

Its still giving me the AVG Time for both days of 264.

The date table I have uses Date just like in the formula but its giving me the average for all days and not the previous day

[parry2k]

@nosaj03 As a best practice, add date dimension in your model and use it for and time intelligence calculations. There are many posts on how to add date dimension and below is the link to a few. Once the date dimension is added, mark it as a date table on table tools.

https://www.sqlbi.com/articles/creating-a-simple-date-table-in-dax/
https://radacad.com/create-a-date-dimension-in-power-bi-in-4-steps-step-1-calendar-columns

and then you can use something like this

Previous Day SAles = 
CALCULATE ( SUM ( Table[SAles] ), DATEADD ( CalendarTable[Date], -1, DAY ) )

I would ❤ Kudos if my solution helped. 👉 If you can spend time posting the question, you can also make efforts to give Kudos whoever helped to solve your problem. It is a token of appreciation!