If it is a number, you have to use float (decimal) or interger (whole number) data type when setting up the parameter.
Thanks for your reply while my key issue is how to do...
For example, I want to see the data by changing "race" dimension, which have white, asian inside.
I can easily create a parameter based on this, but the problem is what's the next, how I can connect the parameter with my original dimension.
First change your people dim datatype to string and year as int data type.
Create two parameter with int datatype with year and string data type with people.
Create parameter as [Race Parameter] and then create calc as
Drag this into filter and select true.
Now you get selected race in view.
Thanks It works now!