Hi There, I’m having an issue with a formula. What I’m trying to do is calculate the accuracy of time estimates of my team.

Here are the fundamentals I’m working with:

- Accuracy should be the estimate/actual*100
- If an item doesn’t have a start & end date then the Accuracy should be blank
- If an actual value is lower than an estimate, they receive 100% accuracy

Here is the formula I have put together:

```
IF({Estimate}<{Actual},{Estimate}/{Actual}*100,
IF({Actual},100,
""
)
)
```

The actual column itself is a formula as well:

```
WORKDAYS({End Date},{Start Date})
```

The formulas are working fine, however I get an error for the accuracy column when the start and end date are not filled in:

Thanks in advance!