Week-over-week change $ and %

[mattrixdesign2]

I have data that captues a "snap shot" of a price each week, example (below).

How can I measure week over week change? As a % and $ - I can do some visuals for the trending/direction, but need the ability to capture the detlas in a calculation.

A possible alternative is to transform this into monthly data, and then compare months, but I would have to average the costs some (MODE).

DATE	ITEM	COST
20/03/2022 00:00:00	123456	2.81
27/03/2022 00:00:00	123456	2.81
03/04/2022 00:00:00	123456	2.57
10/04/2022 00:00:00	123456	2.57
17/04/2022 00:00:00	123456	2.57
24/04/2022 00:00:00	123456	2.57
01/05/2022 00:00:00	123456	2.35
08/05/2022 00:00:00	123456	2.25
15/05/2022 00:00:00	123456	2.77
22/05/2022 00:00:00	123456	2.71
29/05/2022 00:00:00	123456	2.71
05/06/2022 00:00:00	123456	2.71
12/06/2022 00:00:00	123456	2.75
19/06/2022 00:00:00	123456	3.08
26/06/2022 00:00:00	123456	3.08
03/07/2022 00:00:00	123456	3.08

[FreemanZ]

hi @mattrixdesign2 

you may add a column like:

CostLastWeek=

VAR _weeknum = WEEKNUM([Date])

RETURN

MINX(

   FILTER(

       TableName, 

       TableName[Date]=_weeknum-1

   ), 

TableName[Cost]

)

[MAwwad]

1. reate a new column for the week-over-week change in cost by using the DIFFERENCE function and setting the second argument to 1 (to indicate a 1-week difference). Syntax : =DIFFERENCE(SUMMARIZE(FILTER(YOUR_TABLE,YOUR_TABLE[DATE] = MAX(YOUR_TABLE[DATE])),YOUR_TABLE[COST]),SUMMARIZE(FILTER(YOUR_TABLE,YOUR_TABLE[DATE] = MAX(YOUR_TABLE[DATE])-1),YOUR_TABLE[COST]),1)

2. Create a new column for the percentage change by dividing the difference column by the previous week's cost and multiplying by 100. Syntax : =[WEEK OVER WEEK CHANGE] / SUMMARIZE(FILTER(YOUR_TABLE,YOUR_TABLE[DATE] = MAX(YOUR_TABLE[DATE])-1),YOUR_TABLE[COST]) * 100

3. Create a new column for the dollar change by subtracting the previous week's cost from the current week's cost. Syntax : =SUMMARIZE(FILTER(YOUR_TABLE,YOUR_TABLE[DATE] = MAX(YOUR_TABLE[DATE])),YOUR_TABLE[COST]) - SUMMARIZE(FILTER(YOUR_TABLE,YOUR_TABLE[DATE] = MAX(YOUR_TABLE[DATE])-1),YOUR_TABLE[COST])

[mattrixdesign2]

Hi - for some reason DIFFERENCE is not a valid function for me, not sure why.