I've just discovered that I can edit the data values in a chart by draging
the points on the graph.
This feature will allow me to use Excel as a simple data entry tool.
But it appears this by-passes the cell validation.

For example if I have a line chart

X Y
10 5
20 8
30 9

I can drag the 2nd point to any value.

What I want to do is limit it to be within the 2 values surrounding it.

i.e. 10<X2<30 & 5<Y2<9

Does anyone have any idea how I can achieve this? I've tried searching for
this in a number of places, but nowhere seems to mention the ability to drag
points about. Even knowing the 'official' name for this feature would be an
aid to continue searching.


Cheers

DAve