combine 2 date fields on one axis

[Xiphias]

Hi,

Hope someone can help me with a chart problem which I can't figure out...

I have a table with 2 date fields like below:

RMA DateIN DateOut
1 1-1-2011 2-2-2011
2 1-1-2011 3-3-2011
3 2-2-2011 3-3-2011
4 2-2-2011 4-4-2011
5 3-3-2011 5-5-2011

The chart that I would like, should look like this: (ignore the dots)

I = amount of InComing units
O= amount of OutGoing units

5
4
3
2 ..I... I.... O
1 .......O... I... O... O
...Jan Feb Mar Apr May


I cant get it to work

Could someone assist with this?
Thank you!