Crystal Report with parameters

Question

I have simple Crystal Report in which i am showing data from five tables they are joined , I also added a parameter field into my crystal report , The problem is that When my report load first time it does not takes time, but on paging and on selecting the parameter from the list it will take longer longer time , I am not using any code in vb.net code behind i am directly binding the report with the database fields using report Wizard....

 

Any one give assistance ...Would be appreciated