用fastreport计算正常比率结果总是出不来 求教

我想计算 正常比率


 [SUM(<jbtj."zctj">)]/(IIF(SUM(<jbtj."yctj">+<jbtj."zctj">)=0,1,SUM(<jbtj."yctj">+<jbtj."zctj">)))*100  #n%2.2f] %  [SUM(<jbtj."zctj">)]/(IIF(S