How to keep a static value btween two points on a chart line instead of a gradual incline

[ks100]

I have a pivot chart that plots dates on one axis and an arbitrary value on another.


For every line I add (lines are projects) there are three points:

Project Start, whose Y axis number is always a 10
Project Report, whose Y axis number is always a 20
Project End, whose Y axis number is always a 30

the points are always in that chronological order.

The problem is that when I do a line chart there is a gradual incline before the start date, a gradual increase between the project start and project report, and a gradual decrease after the project end.

What I want is for the line not to even exist a day before the project start, or a day after the project end. The project is not worked on before the start date or after the end date, so having a line that inclines/declines before/after those dates does not make sense.

It also does not make sense for the line to gradually increase between start and reporting (value 10 to value 20) because the values on the dates in between those two points are all 10 values, and only become 20 on the reporting date.

So if

Project start: Jan 1
Project Report Mar 1
Project End Apr 1

The line assumes the values would be

Jan = 10
Feb = 15
Mar = 20
Apr = 30

This is not accurate. In reality it is more like

Jan = 10
Feb = 10
Mar = 20
Apr = 30

Short of manually adding a 10 value for each month between the start and report dates (and adding a 0 value for the month before and after the project start/end), is there an easier way to tell a chart line to maintain a static value between two points, and to not have the line exist before the start date or after the end date?

[Richard Buttrey]

Any chance you could upload the workbook so that we may see the request in context.