Scatter Chart Bubble Size

Hi FlowViz 

Download PBIX with these examples

Yes you can use this measure for bubble size

Bubble Size = CALCULATE(COUNTROWS('Table'), FILTER(ALL('Table'), 'Table'[CycleTimedays] = SELECTEDVALUE('Table'[CycleTimedays]) && 'Table'[DaysSinceCompleted] = SELECTEDVALUE('Table'[DaysSinceCompleted])))

To give this

You might also consider introducing jitter to one of the axes to shift overlapping points slightly.

This measure shifts the x value slightly for points that overlap.  It uses the [Bubble Size] measure from above.

Jittered X = IF([Bubble Size] > 1, SELECTEDVALUE('Table'[DaysSinceCompleted])*(RAND()), SELECTEDVALUE('Table'[DaysSinceCompleted]))

Giving this visual.  The amount of jitter/shift for each point can be tweaked so it's not shifted too much.

Further info on jitter Jitter in Excel Scatter Charts • My Online Training Hub

Regards

Phil