Issue with Filter Expression using calculated Object

Dear Experts,

I have a projection inside a calculation view , This Projection has Input Parameter $$IP_FiscalYear$$ which accept year from user. This Input parameter is propagated to semantic layer.

I want to restrict this projection for previous year data So I have created following two calculated column objects at projection level -

InputYearStartDate = '$$IP_FiscalYear$$ + '0101'

PreviousYear = leftstr(string(adddays(date("InputYearStartDate"),-1)),4)

Now I have created a Expression Filter for projection on dimension object FiscalYear with Filter condition defined as below to restrict previous year data-

"FiscalYear" = "PreviousYear"

I could not see the data in preview. (tested with input parameter value = 2016 to see previous year i.e 2015 data).

However I could see the data and above two calculated variables if I filter expression with Input parameter

value  as - "FiscalYear" = "'$$IN_FiscalYear$$' (this will show the data for same input parameter year).

Could you please guide me whats wrong here when using calculated column in Filter Expression. Please note that all the Objects here are defined as NVARCHAR.

Thanks & Regards,

Jiten