SAMEPERIODLASTYEAR DAX Function
The SAMEPERIODLASTYEAR function returns a single-column table with single value of date shifted one year back in time from the dates in the specified dates column, in the current context.
DAX Syntax SAMEPERIODLASTYEAR(date)
The parameter date is a column containing dates.
Example: Create a measure.
DAX
Sum of Sameperiodlastyear income = CALCULATE(SUM(Sheet8[Annual Income]), SAMEPERIODLASTYEAR('Sheet8'[Year]))