Expressions to be added in the parameters default value:
Yesterday Date
="[Date].[Date Hierarchy].[Date].&[" & Today().AddDays(-1).ToString("yyyyMMdd") & "]"
or
="[Date].[Date Hierarchy].[Date].&[" + Format(DateAdd("d", -7, Now), "yyyyMMdd") + "]"
Current Month
="[Date].[Date Hierarchy].[Month].&[" & Today().ToString("yyyyMM") & "00]"
or
="[Date].[Date Hierarchy].[Month].&[" + Format(DateAdd("d", -1, Now), "yyyyMM") + "00]"
or
="[Date].[Date Hierarchy].[Month].&[" + Format(Now, "yyyyMM") + "00]"
Previous Month
="[Date].[Date Hierarchy].[Month].&[" + Format(DateAdd("m", -1, Now), "yyyyMM") + "00]"
If you will be using either the parameter value above in your stored procedure for the report, you can use a function to SplitDelimetedString to get the datekey and do a lookup using IN. The udf.SplitDelimitedString function can be copy from SQL Funtion section of this Eblog Site
DECLARE @parmDate VARCHAR (MAX) = '[Date].[Date Hierarchy].&[20121129]'
AND Datekey IN
(
SELECT DISTINCT REPLACE(RIGHT (CONVERT (VARCHAR (50),([Value])), 9),']','')
)
FROM udf.SplitDelimitedString (@parmDate,',')