I have a simple chart set up that references data points which are
vertically ten spaces apart.  The chart has worked fine for months.
However, when I went to update it with another series point today it
simply will not "OK" the extra point.  I click enter, I click okay,
and NOTHING.  It's not just one chart that this is happening with,
either.  In the same file I have another chart that references another
point that is spaced like the previous one but I have the same
problem.  I've never had this happen before and tooling around with it
hasn't yielded any fruit.

Some sagacious wisdom would be MUCH appreciated.

Thanks.