Add parameter to SSRS Report business logic.

I am using SSRS for AX 2012.

One of report using Business Logic for the datasource type.

The business logic look like:

[DataMethod(), PermissionSet(SecurityAction.Assert, Name = "FullTrust")]
public static DataTable getAccountNum() 

...

but I want to pass a parameter (or use a global parameter) in that method.

How can I do that?