How to remove space in a combo chart

[raynac]

Hey all!  I have a combo chart that's giving me grief.  All of my others are fine but this one has this strange gap under the bars.  Can anyone tell me how to remove all this space that's coloured in the fuchsia pink and get my bars down to the bottom where they belong? There's no negative data, so that's not the issue.

The only setting that seems to help is the Log Scale setting, but if I turn that on, the bars are no longer proportional to the numbers they represent.

Thanks for any help you can provide!

[Or]

This looks like a split axis chart, so I'd try playing around with the settings for that.