You got some screenshots? Are you sure holiday sales are 0 or are they null? If it is literally null, the calculation wouldn't operate the subtraction. Either way, you would be better off by giving us some sample data.
There are nulls that I already converted to 0 using the LOOKUP(ZN(SUM([ Net Amt (USD)])),0)
However, I cant use the newly created calculated measure above to create measures for Holiday and Fall separately.
So my initial measure is "Net Amt USD".
It has several nulls which is essentially 0.
So I used the function LOOKUP(ZN(SUM([ Net Amt (USD)])),0) to replace the nulls with zeros.
Then I tried to pull out just the Holiday Sales (Net Amt USD) using this calculation. IF [Season] = 'Holiday' THEN Net Amt USD (the new calculated field replacing the nulls with zero), but it doesn't work, the calculation shows an error.
However, if I pull out Holiday sales using the INITIAL Net Amt USD measure it works. But when I use the 2 newly created measures (Holiday Sales, Fall Sales) to minus off each other.
I try every way but my negatives show as 0.
Excuse the interruption...
Is there a reason you are using the LOOKUP() function? Its likely to have been set up wrongly, and therefore is affecting the rest of your calculation.
Something like this, should be sufficient - ZN(SUM([Net Amt (USD)]))
Otherwise, if you could mock up some basic numbers in Excel (to replicate the problem), it would be easier to help!
I can mock up an example, but i dont know if it will help.
Are you using 9.2.4?