how to resolve #Multivalue Error

HI All,

I have a data like below, in this for inpatient data is NULL and as per business requirement  if data is null then "0". so i create a variable and drag into inpatient's total column

statement for inpatient is

=If IsNull([total]) Then 0 Else [total] Where ([items]="Inpatient")

items                                    total

it is working and showing as "0"

but when inpatient has value it is showing #multivalue"

how to resolve is issue

Please reply i am using SAP BO 3.1 INFOVIEW

Thanks in advance

Ranjeet