[crystal-reports] How to calculate sum of a formula field in crystal Reports?

You Can simply Right Click Formula Fields- > new Give it a name like TotalCount then Right this code:

if(isnull(sum(count({YOURCOLUMN})))) then
0
else
(sum(count({YOURCOLUMN})))

and Save then Drag and drop TotalCount this field in header/footer. After you open the "count" bracket you can drop your column there from the above section.See the example in the Pictureenter image description here