Calculated field in pivot to sum on positive number & another for negative numbers

i think i have a very simple problem i cant seem to work out! I have a pivot table with 2 calculated field. I am trying to sum only positive numbers and sum only negative numbers in the second field. The formula depicted is know is not correct. I have tried =SUMIF(‘Change’,”>0″) & =SUMIF(‘Change’,”<0″) but both dont work for some reason. Any idea whats wrong? Thank you
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