How do I get Excel to run a macro without showing all intermediate steps in a calculation? So, after I kick off the macro, there are no changes on the screen until the macro has finished...

I’m trying to plot more than one series on a chart, but I will never know in advance how many series’ will need to be plotted at runtime.
 
I’ve got the code to add the chart and 1st series in Module1.addChart
 
The problem at the moment is my Module1.addSeries, because there is no active chart.  I’ve tried code to activate / select the chart first, but it’s not having it.
I coded it this way, because before addSeries is called, it adds the actual chart, and I thought the chart was still active.
So I figured passing the chartobject as a parameter would be the best bet.