Please refer the attached workbook. I have created a parameter "Assumption" and a calculated field "New Count". As the user changes the parameter value, the calculate field will change the value. However, please note that we can only create new columns to the existing data in Tableau and can not insert a new row. ( Unless some smart kid or old fox comes with a hack!!). If you want to recalculate the ratings , you need to create a new calculated field for that.
Book1.twbx 21.5 KB
Thanks for your help. The calculation you recommended will work.
Thanks again for your quick turn around.