Pivot Table

[GraceGao]

Hi Experts,

I would like to add one column before the monthly sales as below screenshot. could any way to achieve this? Thanks.

[OmarBenSalem]

I'll assume this is your data : 

Load * Inline [

Year, Measure, Month , Produt
2020 , 100 , 1 , A
2020 , 300 ,2, A
2020 , 400,3, A
2020 , 300,4, A
2020 , 600,5, A
2019 , 200,1, A
2019, 300,2, A
2019 , 500,3, A
2019 ,100,4, A
2019 , 1000,5, A

2020 , 360 , 1 , B
2020 , 300 ,2, B
2020 , 700,3, B
2020 , 800,4, B
2020 , 900,5, B
2019 , 200,1, B
2019, 320,2, B
2019 , 600,3, B
2019 ,150,4, B
2019 , 900,5, B

];

Create a pivot table : 

as line Product

as columns : Month, Year

as a measure : sum(Measure)

Now, create as a second line :

=num(aggr((Sum({<Year={"$(=max(Year))"}>}Measure) -
Sum({<Year={"$(=max(Year)-1)"}>}Measure))
/
Sum({<Year={"$(=max(Year)-1)"}>}Measure),Produt),'# ##0,00%')

this will be your CY vs LY% 

For it to be, uncheck this : 

and here you go :

[GraceGao]

can display total %?