Percent change (WoW, MoM, etc) as a trending line in card.

Hey EJRM!

I went ahead and put together some beast modes that I hope will be helpful for you. My test data is at the month granularity, but the principles should work regardless of what date grain your data is at.

Date Alignment: (This is to align the dates from last year and this year, so if you filter the graph to only this year, you don't lose any data. Basically turns 2016-01-01 into 2017-01-01)

Case when year(`Date`) = YEAR(CURRENT_DATE())-1 then DATE_ADD(`Date`, Interval 1 Year)
Else `Date` END

This Years Sales: (This is to be used in the bar in the bar+line graph, since we aligned the dates, we don't want to count last years sales as this year's sales, so this excludes last year by date)

SUM(Case when YEAR(`Date`) = year(CURRENT_DATE()) then `Sales` end)

(Optional) Last Years Sales: (In case you want to see last year sales alongside this year with a percentage change line. 

SUM(Case when year(`Date`) = YEAR(CURRENT_DATE()) -1 then `Sales` END)

YoY % Change: (Calculation This year - Last year / Last Year)

(SUM(Case when year(`Date`) = year(CURRENT_DATE()) then `Sales` END)

-

SUM(Case when year(`Date`) = (year(CURRENT_DATE())-1) then `Sales` END))

/

(SUM(Case when year(`Date`) = (year(CURRENT_DATE())-1) then `Sales` END))

Screenshot of final product:

Hope this is helpful! Let me know if you need additional clarification or if you have additional questions.

What card type did you use?