Getting wrong data into drilldown SSRS report

I created a SSRS drilldown report ,the report can be drill based on year ,Quarter
 and month name.I am showing the total percentage for year,Quarter and month name
baesed on requirement.Initially when i am not clicking the plus sign(+) the total % getting
wrong but when i clicked on plus sign(+){to drill the report} getting correct data .i am not performing any type of calculation at SSRS level the data i am getting from cube only

This is wrong data

.                            (+)2011  (+)2012
          
         
        %TOtal Work  50         75
        %Rework       35         45
        %Done          60         78

This is correct data

                     (+)2011   (-)2012
                                                  Q1      Q2     Q3  Q4
         
  %TOtal Work 50          73.33   
  %Rework      35            33
  %Done         60             58                                                                                                 when i am clicking + or  - sign to drilldwon report the data automatically changed how to resolve this problem.