Calculate difference using a ranking column

[unusdusrname]

Hello all. I have some cumulative sales data which publishes every week, and I need to figure out the delta in such a manner I can easily target the larger books/debooks. Lets say my data look like this:

Group	SubGroup	Continent	Country	Sales	Week ending	Order
Fruit	Apples	Africa	Zimbabwe	100	21/07/2023	3
Fruit	Apples	Asia	Fiji	120	14/07/2023	2
Fruit	Oranges	Asia	Vietnam	300	7/07/2023	1
Fruit	Apples	Asia	Fiji	250	21/07/2023	3
Veg	Carrots	Australasia	New Zealand	10	14/07/2023	2
Veg	Carrots	Europe	Czech Republic	150	7/07/2023	1

Subgroups are always subsets of groups, and countries are always subsets of continents. The week ending field is text and tends to get a bit freeform, so I'm generating the 'Order' column where oldest is smallest and the week ending:order relationship is 1:1. The sales number is cumulative of all prior weeks/'orders' in the dataset.

In this example we can see that in the last week we've sold 130 fijian apples, and it's this number I wish to calculate to display in a matrix that the user can drill into .

I previously asked a similar question and tried to modify that to suit my new question, but I'm missing a fundamental concept as while my totals are correct, the values at a continent/country level are preposterously large

Thanks 🙂

[amitchandak]

@unusdusrname , A column that can give you week sales from cumulative

sales this week=
var _date = maxx(filter( Table,[Group] = earlier([Group]) && [SubGroup] = earlier([SubGroup]) && [Continent] = earlier([Continent])
&& [Country] = earlier(Country) && [Week ending Order] < earlier([Week ending Order])),[Week ending Order])
return
[Sales] - Sumx(filter( Table,[Group] = earlier([Group]) && [SubGroup] = earlier([SubGroup]) && [Continent] = earlier([Continent])
&& [Country] = earlier(Country) && [Week ending Order] =_max ),[sales])

Measure to compare this week vs last week

Week Rank = RANKX('Date','Date'[Week Start date],,ASC,Dense)
OR
Week Rank = RANKX('Date','Date'[Year Week],,ASC,Dense) //YYYYWW format

These measures can help
This Week = CALCULATE(sum('Table'[Qty]), FILTER(ALL('Date'),'Date'[Week Rank]=max('Date'[Week Rank])))
Last Week = CALCULATE(sum('Table'[Qty]), FILTER(ALL('Date'),'Date'[Week Rank]=max('Date'[Week Rank])-1))

to get the week start/week end of Friday, refer

2.Any Weekday Week - Start From Any day of Week
https://community.powerbi.com/t5/Community-Blog/Any-Weekday-Week-Decoding-Date-and-Calendar-2-5-Powe...
https://medium.com/chandakamit/cheat-sheet-any-weekdays-week-start-date-just-one-variable-apart-6b2e...

[unusdusrname]

Thanks Amit. I didn't quite get your code to work however, PowerBi reports syntax errors.

So I expunged the surplus carriage returns, and added the square braces around [Country]. I also changed [Week Ending Order] for just [Order] as those two were different fields.

I've still got a syntax error in the return clause where [Order] = _max - am I right in thinking _max is intended to be a variable that's been defined? So it maybe ought to be _date defined in the var clause above? Here's what I tried.

sales this week = 
var _date = maxx(filter( Table,[Group] = earlier([Group]) && [SubGroup] = earlier([SubGroup]) && [Continent] = earlier([Continent]) && [Country] = earlier([Country]) && [Order] < earlier([Order])),[Order])
return
[Sales] - Sumx(filter( Table,[Group] = earlier([Group]) && [SubGroup] = earlier([SubGroup]) && [Continent] = earlier([Continent])&& [Country] = earlier([Country]) && [Order] =_date ),[sales])

 Just gotta love how PowerBI won't share even which line holds the supposed syntax error. Can you see what is wrong?