Cross Tab Report getting #Multivalue error when aggregation happens

Hi,

I am working on Web I report using the BEx query as a source. I have created a variable with in the report to consider few records has to be considered  as a single record and used the same in cross tab getting the #Multivalue error.

for ex: I have the following records getting from the query

Dimension     Measure

X1                    10

X2                    20

Y                     40

I want to consider X1 and X2 as X and need to show the aggregate values in the report. Required result would be:

X     30

Y     40

For considering X1 and X2 as X created a variable and used in the cross tab, dimension value is showing as X but getting the #Multivalue error for Measure.

Variable definition: If left(Dimension;1) = X then X else Dimension used this in cross tab.

Getting the following results:

X     #Multivalue

Y     40

Tried to check the check box "Avoid Duplicate records" in table properties getting the following result

X     10

X     20

Y    40

but I need the value to be aggregated and X can not be repeated twice, calculated the measure using the following formula

Measure_V = Sum(Measure) foreach(Dimension) getting the following results:

X     30

X     30

Y     40

here the values are aggregated but need to show the X value as one record in the report.

Tried to hide the duplicate record using the formula

V2 = Runningcount(Dimension;(Dimension))  this variable is a measure if I used in the report getting the following result

     V2

X     1     30

X     2     30

Y     1     40

Tried to apply the block filter to show the V2 = 1 but this does not help me in my case.

Please share your valuable inputs to solve this issue.

Thanks in advance,

Mallareddy D.