I am working on a Project S-curve for a customer, based off % complete (X axis) and dates\ (Y axis). The problem I am running into is that the data points don't all share the same dates. As an example:

Baseline Date - Baseline % - Planned Date - Planned % - Actual Date - Actual %
1Feb12 - 12% - 4Feb12 - 8% - 4Feb12 - 8%
14Feb12 - 24% - 12Feb12 - 22% - 12Feb12 - 22%
29Feb12 - 36% - 1May12 - 38% - (No Data)


I know I can chart a series of lines in a single chart, if the dates (Y axis) were consistent. However, when the Y values are different for each data point, how do I create a line for each set of data, again, using % Complete as the X-Axis and Dates as the Y-Axis?

Thank you very much for the help.