Jon Peltier has two solutions for you at his site:

http://peltiertech.com/Excel/Charts/...l.html#XYArea2

http://peltiertech.com/Excel/Charts/...ll.html#XYArea

Robert Flanagan
http://www.add-ins.com
Productivity add-ins and downloadable books on VB macros for Excel

"txgweedo" wrote in message
...
I'm new to XL 07 and I'm trying to add color shading to a specific part of
the plot area based on the y axis. I've tried adding a new series but XL
says my line chart is too complex. I'm charting blood sugar levels taking
at
different times each day. I want to color the range from 80 to 120 as a
'target level' across the chart. Please help if you can!