Merging Axis, but not ALL axis

Merging Axis, but not ALL axis

Is there a way to merge only some of the axis on a report ?

I have a report, where I'd like to display
- Cohort revenue averages 
- Cohort revenue summations
- Cohort Count


And I want 2 axis, one for the "Cohort Count" and a merged one for the two revenue data series.

It seems to me that merge axis is either all or nothing.  Is there a way to merge axis for only subset of data series?

Thanks.