PREVIOUSYEAR Returns a table that contains a column of all dates from the previous year, given the last date in the dates column, in the current context.
Syntax
PREVIOUSYEAR(dates[,year_end_date])
Parameters
Dates – A column containing dates.
Return Value
A table containing a single column of date values.
Reference Data
https://docs.microsoft.com/en-us/dax/dax-function-reference