+1 for this feature 
In our case, we have:
- A board with multiple groups, recording sales by type
- A board recording lost sales
We have a dashboard that has a number widget that sums up all groups to give us the total figure. E.g. Product 1 (group) = £10, Product 2 (group) = £20, therefore total sales = £30. And the same for business lost, for example, total lost = £3.
It would be extremely useful to be able to calculate those two dashboard widgets as a %, so the ‘Lost Business’ widget would report 10%.
There isn’t an easy way to do this in boards and it doesn’t justify the mess of an entire board. The ability to calculate %s is so important to reporting.
Thanks guys!
Alex