Your data is like

           actual    projected
1-jan-07      100          0
2-jan-07      110          0
3-jan-07        0          120
4-jan-07        0          130

so you have a line in the actual series from {2-jan-07, 110} to {3-jan-07,
0}, which slopes downward, and another in the projected series from
{2-jan-07, 0} to {3-jan-07, 120}, which would slope upwards, except it
nicely fills in next to the downward sloping line.

Keeping a time-scale axis, change your data like this, so you have two
points for each series on the date where the vertical transition belongs:

           actual    projected
1-jan-07      100          0
2-jan-07      110          0
2-jan-07        0          110
3-jan-07        0          120
4-jan-07        0          130

The lines are now defined at {2-jan-07, 110} to {2-jan-07, 0} and {2-jan-07,
0} to {2-jan-07, 110}, with both endpoints on the same date, thus they are
vertical.

- Jon
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Jon Peltier, Microsoft Excel MVP
Tutorials and Custom Solutions
http://PeltierTech.com
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