SSRS does not support the sharing of expression between multiple reports.
Best you can do is building the expression in a sub report and call that sub report in all the dependent reports. Then you have a single point where you can do the changes to your expression.
- Proposed as answer by Charlie LiaoMicrosoft contingent staff, Moderator Tuesday, April 02, 2013 8:11 AM
As Harsh said, sharing expression between multiple reports is no support in Reporting Services currently. If you have any concerns about this feature, you can submit a feedback at http://connect.microsoft.com/SQLServer/Feedback and hope it is resolved in the next release of service pack or product.
Thank you for your understanding.
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