How to pass multiple values to dashboard prompt?

Hello Gurus,

I am working on BO Dashboard 4.1 with HANA as source.  I have a query on dashboard with YEAR as one of its attribute.  I am having current year and previous year in dashboard excel sheet, and I want to pass these 2 year values to the query.  So, I have created an optional prompt for YEAR in my query with type as IN LIST.  Now, how can I pass those 2 cells from my excel to dashboard query?

I also tried C1,C2 and C1;C2, but its not accepting those values.

Can any of you experts help me on this?

Thanks

RJ