I'm a relatively new Tableau user and haven't been able to figure out how to properly create a calculated index in a table based on the value in the Grand Total. The values for Index in the image below are incorrect. For example, the first row in the (blinded) Network field shows a Pivot Field Value of 16%. I'd like the Index field to return a value of 67, based on the comparison to the Pivot Field Value average shown in the Grand Total ((16%/24%)*100). Likewise, the second row in the Network field should show an index of 117 ((28%/24%)*100). It's also important that the Index change based on different returns based on my filters (so if I select different criteria based on my filters, the Index is always calculated based on the different networks, grand totals etc. that would result from the filters).