VERY URGENT - WoW calculation is not working

[mohan_g_das1986]

Hi - I am having data for FY18 & FY19 by weekly level. by using the below salesprioryear, i can able to show the YoY, QoQ, MoM data. But WoW is not happening shows blank.

how should we calculate it? Attaching screen shots

SalesPriorYear = CALCULATE([Total ST_units], SAMEPERIODLASTYEAR(Calendar_time[Date]))

- 

[jdbuchanan71]

@mohan_g_das1986 

If you select 2018W26 under the week, what shows under Cur.Year Units?