Why you are not trying COUNT([Side]). If there is anything else, please share the workbook.
Hi David - I agree that it would be easier to understand it we could see your workbook - that said the formula has a couple of issues
COUNT(IF([Side]='Buy'>0 and [Side]='Sell'>0)
In the first line Side = cannot at the same time (record) have a value of Buy and a value of Sell - so all records will fail the If check
If you are trying to eliminate records that don'f have either but>0 or sell>0 the formula would be
IF([Side]='Buy'>0 Or [Side]='Sell'>0) then 1 else 0 end
then you would aggregate the formula as a sum when yo place it on the viz
Let me know if this helps