The SAMEPERIODLASTYEAR() function returns a table that contains a column of dates shifted one year back in time from the dates in the specified dates column, in the current context. It means this function will go to find the last year for each date in your calendar table. That's why you got the duplicated number and the data started from many years before 2016.
Since you just want to get the last year values. I think you can try following method:
Total Sales previous Year =
SUM ( INVOICE[ITEM_TOTAL] ),
YEAR ( INVOICE[DATE_ISSUED] )
= YEAR ( MAX ( INVOICE[DATE_ISSUED] ) - 1 )
Same to current year or monthly, weekly.
If above method doesn't satisfy your requirement, could you please share us your desired result based on your sample data if possible?