Month on Month

[n1ef5ng1]

I need to make a month on month comparison(i.e Mar 2012 - Feb 2012, Jan 2012 - Dec 2011 data on pivot table, this is the code on my dimension to extrapolate the value on the current month, therefore Month_Year have to be on the dimension

=IF ( Date > AddMonths (  ( var_EndDate ) , (-var_PeriodInYears * 12) ) ,

if( MonthEnd(Date) <> var_EndDate

AND MonthEnd(Date) = MonthEnd(var_EndDate)

, '*' & Month_Year, Month_Year) )

This is my code for my expression

=if( MonthEnd ( MAX( Date ) ) <> var_EndDate AND MonthEnd( MAX ( Date ) )
= MonthEnd( var_EndDate ) ,

(

(
  sum({$<Year = {$(v_ThisYear)}, Loading = {'ID*'}>} TEU)
  -
  sum({$<Year = {$(v_ThisYear)},Loading = {'ID*'}>} TEU)
)

/ Day( var_EndDate )) * Day(MonthEnd(MAX ( Date )) * 100

)

,

((sum({$<Year = {$(v_ThisYear)},Loading = {'ID*'}>} TEU)
-
sum({$<Year = {$(v_ThisYear)},Loading = {'ID*'}>} TEU)))

)

I am thinking of using this code to make MOM comparison but it is not working

AddMonths(Date,-1)

Is there any code that works something like this?