How do I use a Page Parameter with a Chart or Panel?

How do I use a Page Parameter with a Chart or Panel?

I am trying to feed in a page parameter to a panel's record criteria.

I used ${page_parameter_name} in the criteria field, which doesn't work.

Will I have to use a ZML snippet to achieve this?

criteria='(((Confirmed == "$(confirmed}")))'

What is the correct way to modify this ZML to achieve this?