How to get sum of sales for the same day of the week from years past.

[Zntz]

Hello.

I am sure it is possible, but I wanted to know how I can manipulate a table, so it shows the sum of sales of the same day of the week of past years.

type	2018-08-15	2019-08-14	2020-08-12	2021-08-11
	Wednesday	Wednesday	Wednesday	Wednesday
Fitness				200
Running		113		30
Soccer	3		58

My data are in vector format. e.g.

4-year history and those that accumulate.

date	type	sale
11/08/2021	Fitness	200
11/08/2021	Running	30
12/08/2020	Fitness	58
14/08/2019	Running	113
15/08/2018	Soccer	3

Best regards.

[lironbaram]

Hi, 
Have a look at the attached app for an example 

[Zntz]

Hi!
I have tried this by when I add more data to the vector it does not return only the day of the week of previous years.

table1:
load * inline [
date, type, sale
11/08/2021, Fitness, 200
12/08/2021, Fitness, 100
13/08/2021, Running, 50
11/08/2021, Running, 30
11/08/2020, Running, 222
12/08/2020, Fitness, 58
13/08/2020, Fitness, 116
13/08/2019, Fitness, 40
14/08/2019, Running, 113
15/08/2019, Running, 100
14/08/2018, Fitness, 9
15/08/2018, Soccer, 3
16/08/2018, Soccer, 6

];

Thank you.

[lironbaram]

Hi, 
please have a look at the attached app