I have 9,000+ data points that need to be in an X Y Scatter Chart. About 50%
only have an X Value, but the absence of the Y Factor is important data. It
represents no actions were needed for a 6 month period of time.

If I remove those missing the Y Factor, the time spent is overstated. If I
place a zero, Excel doesn't like it. I have inserted a .0000001 for the
missing Y Factor and then I get a misrepresentation the opposite way.

I have added all the values and averaged for a single point and non of the
plots or computed trend-lines hits the mark.

Am I going about this wrong and is there an accepted practice for missing
values?

Thanks

Dave