I think you are looking for conditional formatting. Format -> Conditional Formatting… You can assign many aspects of a cell’s format based on another cell’s value or how a formula evaluates (to TRUE or FALSE, not a value)

There are workarounds to get the plotting rectangle (the plot inside area) to stay put. These include not using the built-in axes, but building your own, using XY series data labels for axis labels. Changing of these labels has no effect on how Excel feels like resizing the plot area. Here are some examples:

http://peltiertech.com/Excel/Charts/ChartIndex.html#AxisScales

Most of the workaround methods that various clever people have devised use things like line series, date-lines, and categories to do things (like shading between lines for instance). These don’t work for the y-axis. I’d like to see the same functionality for y-axes as for x-axes.

I’d also like to be able to be able to control things like axis length and position so that when you create a series of plots with different scales (as would appear in an engineering report on different material property profiles), the plots don’t move around the page as you flick through the printed report. Presently if you change from an axis of scale say 0-10 to one of scale 0-1000 the whole axis moves in order to accomodate the longer label.

Kevin isn’t hiding rows, he’s narrowing the range of an axis, so points with values outside that range are not visible. But they’re still part of the series, so they affect the auto scale of the other axis.

Kevin -

One trick is to hide rows containing X values outside of your range, which is how John approached your issue. Try an autofilter.

Another approach would be programmatic. Your code would determine which points fell within the X range, find the minimum and maximum Y values for those points, then calculate and apply appropriate Y axis scale parameters.

I created an XY chart, then hid some rows. The chart scaling adjusted to the visible data only.