always display 10 major gridlines for y axis in graph

Hi,
I have graphs where I can never be sure of the range of values that
will be displayed. How would I set it to show 10 major gridlines on
the y axis' I tried setting the interval to 0.1 but this ovbiously
didn't work as the graph shows monetary values? And I can't set an
explicit interval as I won't know the max value to split in 10?
Can anyone tell me how to do this please' I'm using RS 2000
Thanks,
Gear=F3idcan anyone help with me this no? Desperate to get it done today...
Thanks...