"Incorrect" Percentage Roll Ups in Power View and Power Pivot

[IanNRobertson]

I am working with Excel 2013 on a W8 machine and am using Power View / Power Pivot to visualize achieved production versus forecasted production data. The data I have tracks production that occurs at multiple sites each calendar day. In the report I am trying to show actual production as a percentage of forecasted production. To do this, I have added a column in the Power Pivot table and added a calculation that divides actual production by forcasted production (i.e. actual production / forecasted production). When I add this field to a tabular report in Power View, it reports the expected result when the detail is at the lowest level - i.e. production reported by site by day. However, if I remove day from the report view and leave only site, I am getting a sum of the percentages and not a percentage of the sites total actual production versus total forecasted production. I realize that this is exactly what should be happening as Power View thinks it is supposed to sum the value but this is not what I want to see and I have not been able to figure put how to make the percentage calculation "dynamic" based on what members are selected in the report table.

The below table is some sample data. Currently, if I remove day from the Power View tabular report that is based on this dataset, the % Actual Production to Forecasted Production value is a straight sum of the %'s or 300% for Site A and 190% for site B. The answer I am looking for is 90% for site A (Total Actual production of 45 / Total forecasted production of 50) and 50% of Site B (Total Actual Production of 40 / Total Forecasted Production of 80). Any ideas on how I can add a calculation(s) to my Power Pivot table to accomplish this would be much appreciated.[TABLE="class: grid, width: 500"]
<tbody>[TR]
[TD]Site[/TD]
[TD]Day[/TD]
[TD]Actual Production[/TD]
[TD]Forecasted Production[/TD]
[TD]% Actual Production to Forecasted Production[/TD]
[/TR]
[TR]
[TD]A[/TD]
[TD]M[/TD]
[TD]10[/TD]
[TD]20[/TD]
[TD]50%[/TD]
[/TR]
[TR]
[TD]A[/TD]
[TD]T[/TD]
[TD]20[/TD]
[TD]20[/TD]
[TD]100%[/TD]
[/TR]
[TR]
[TD]A[/TD]
[TD]W[/TD]
[TD]15[/TD]
[TD]10[/TD]
[TD]150%[/TD]
[/TR]
[TR]
[TD]B[/TD]
[TD]M[/TD]
[TD]5[/TD]
[TD]5[/TD]
[TD]100%[/TD]
[/TR]
[TR]
[TD]B[/TD]
[TD]T[/TD]
[TD]10[/TD]
[TD]25[/TD]
[TD]40%[/TD]
[/TR]
[TR]
[TD]B[/TD]
[TD]W[/TD]
[TD]25[/TD]
[TD]50[/TD]
[TD]50%[/TD]
[/TR]
</tbody>[/TABLE]