Dashboard and Bex reports values are differnt

Hi,

I had created Dashboard using Bex reports(Dashboard source is Bex),Dashboard i am passing month and year to Bex reports it will give   12 month data with cumalative,,

Bex following variable i am using with

Plan01,Actual01,Plan02,Actual03,Plan04,Actual04........Plan12 ,Actual12

Plan01 is value of Dashboard month year(.ie 09.2014 if i pass this date and month from dashboard dashboard  )

Actual01 is value of Dashboard month year(.ie 09.2014 if i pass this date and month  )

Plan02 is value of previous all month cumalative value (plan01+plan02 .ie 09.2014+10.2014) this is  calculated from bex

Actual02 is value of previous all month cumalative value (Actual01+Actual02 .ie 09.2014+10.2014) this is  calculated from bex

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Plan12  is value of previous all month cumalative value(plan01+plan02+plan03+plan04+plan05+plan06+plan07+plan08+plan09+plan10+plan11+plan12

Actual12  is value of previous all month cumalative value(Actual01+actual02....Actua12)

here plan01 and actual 01 is Displaying correct value after that it is showing wrong value

for example value of plan01 =100 actual01= 200 plan02= 0.0 actual02 =.0.0.

Dashboard output should come plant02 value is 100(100+0.0)

                                                   Actual02 value is 200(100+0.0)

but is giving plan02 is 200

                    actual is 400

please suggest me what is issues