Help with Trailing 12 months

[alexcastorena]

Hello friends,

I'm reaching out for some help, I'm trying to get trailing 12 months based on the data below.
My most current period is 202009. Trailing 12 months should give me 201910 thru 202009. 
Any help in writing the set analysis is greatly appreciated.

FiscalPeriod	SALES
201901	13,214
201902	14,353
201903	21,208
201904	13,478
201905	14,642
201906	22,104
201907	14,903
201908	15,546
201909	20,605
201910	15,974
201911	16,297
201912	22,911
202001	13,794
202002	14,364
202003	20,860
202004	14,926
202005	13,744
202006	19,176
202007	15,169
202008	15,491
202009	17,819

[Vegar]

What if you try this expression: 

sum(aggr(rangesum(above( sum({<FiscalPeriod=>} SALES),0,12)),FiscalPeriod))

[alexcastorena]

hi Vegar,
i tried that, though it's showing more than 12 months. if possible i would like to select a fiscal period and have the data only show 12 months back from what was selected

[Kushal_Chawda]

@alexcastorena  Assuming your fiscal period is formatted as proper date using Date(Field,'YYYYMM') if not then first convert it and then you can try below

sum({<FiscalPeriod={">=$(=date(addmonths(max(FiscalPeriod),-11),'YYYYMM'))<=$(=date(max(FiscalPeriod),'YYYYMM'))"}>}
aggr(rangesum(above( sum({<FiscalPeriod=>} SALES),0,12)),(FiscalPeriod,(NUMERIC,ASCENDING))))

[alexcastorena]

Hello Kush,

Unfortunately, the fiscal period that i was given is already in YYYYMM, no other date is available.
i tried this set analysis formula, but it only gives me data for 2020

sum({<FiscalPeriod={'>=$(=max(FiscalPeriod)-12)<=$(=max(FiscalPeriod))'}>}Sales)

[Kushal_Chawda]

@alexcastorena  did you try the full expression provided? Seems you are using just part of the expression.

[alexcastorena]

i did try the formula you provided though it did not work