column A: x-values A1:A100
column B: y-values B1:B100
column C: IF(MOD(ROW(),10)=0,b1, NA()); copy down the column

chart A1:C100
The two data sets over lab but C has every 10th point - give it makers
delete/hide B in the chart as you see fit

best wishes
--
Bernard V Liengme
Microsoft Excel MVP
http://people.stfx.ca/bliengme
remove caps from email

"INTP56" wrote in message
...
I have a request to chart data where I only want to display a marker every
n
points, but still see the marker in the Legend.

I can do it by setting the MarkerStyle to a value, then go through every
point in the series and change it's markerstyle to xlNone. However, when
there are 1000's of datapoints per series, this takes a long time.

I can set the MarkerStyle to xlNone, then go through setting every nth
point
to a marker, but then the MarkerStyle doesn't show up in the legend.

I can't seem to set the MarkerStyle in the LegendKey without affecting all
the points in a series.

Does anyone have a way I could see the Marker in the Legend Key, but only
have the marker visible for every Nth point, without having to iterate
through every point in every series?

Thanks,

Bob