I have a chart in Excel 2007 that is basically just a line graph.

Some cells that make up the series data cannot produce a value through their formula, and I'd like the chart to place a gap in that location, but no matter what I do, the fact that there is a formula in there seems to make the series consider this as a zero, or similar.

If I hit Delete on that cell, the gap appears, but when I add a formula, a line that connects the points on either side appears.

Is there any way I can return something with an IF function that produces the gap?

```
IF(somecondition; SUM(...); "")
^^- what to add here, is it possible?
```

The following does not work:

```
IF (somecondition; SUM(...); "")
IF (somecondition; SUM(...);)
IF (somecondition; SUM(...))
IF (somecondition; SUM(...); NA)
IF (somecondition; SUM(...); 1/0)
```

They are all still drawn as though the cell contained 0 (zero).