# SQL Server Reporting Services (SSRS) – IIF statement divide by zero error

If you use the IIF statement to solve your divide by zero errors, you will most likely find that you still get divide by zero errors.

The following example is trying to divide last weeks total hours worked

The following errors:

```=IIF(Sum(Fields!LWWorkingDays.Value) = 0,
0,
Sum(Fields!LWTotal.Value)/Sum(Fields!LWWorkingDays.Value)
)
```

The Problem
Even though the number of days = 0 and it should evaluate to the true condition of 0, SSRS still evaluates the false result, and the false result still throws a divide by zero error because it is evaluating:
Sum(Fields!LWTotal.Value) / 0

The solution:
We need to try to make the false result not error when working days = 0.
The false result

```Sum(Fields!LWTotal.Value) / Sum(Fields!LWWorkingDays.Value)
```

Needs to change to the following:

```Sum(Fields!LWTotal.Value) /
IIF(Sum(Fields!LWWorkingDays.Value) = 0, 1, Sum(Fields!LWWorkingDays.Value))
```

Why does this work?
When working days = 0 the result is going to be 0. So we don’t really care what the false result is going to be we just don’t want it to error. So the new IIF statement on the denominator returns 1 when the working days are zero.

This evaluates to:

```Sum(Fields!LWTotal.Value) / 1
```

and this does not error.

Final Code Example

```=IIF(Sum(Fields!LWWorkingDays.Value) = 0,
0,
Sum(Fields!LWTotal.Value) /
IIF(Sum(Fields!LWWorkingDays.Value) = 0, 1, Sum(Fields!LWWorkingDays.Value)) / 60
)
```

In short by converting the zero to a 1, it stops the false result from erroring and allows the calculation to work correctly when it is evaluated.

That is a work around for a problem that should never of existed, good one Microsoft..