So let's say you have two groups, and you decide to add in the same keywords into two different groups. You may see one, reporting at #8, and the other one might be reporting at #9. The reason for this is that because we do a unique search for both keywords and a separate query on each one, and we don't actually cache any of the data, so we may get two different results.
Depending on the Google Data Center you are connecting to, you may see a slight discrepancy. This is completely normal from what our experiences and it's actually good because it will give you a wider range of results of where your site may be bouncing around. In our experience, if you wait a few days for it to sync and once it stabilizes, this should give you a more granular set of results.
We hope you find this helpful! If you need any further assistance, please contact us and we'll be more than glad to help you out.