Hello Rammohan,
To achieve this, you have to customize the fetch XML of the dashboard on run time. Right now I do not have much idea about to do this but I will do some POC and let you know. Meanwhile, you can also try on this approach.
If my suggestion helps you in solving your issue, kindly do me a great favor by marking it as correct answer. Thanks in advance "Saurabh Gupta, MS CRM 2011 Software Development Engineer"