How to create control chart for more than one observation at the same point in the plot and multiple group.

[rsearch]

Hi All,

I want to create control chart for  data set contain study id, group by,milestone date, and duration between milestone

process a study. As you can see from the data below, several studies get released on the same day. As a result, several

observations could fall on the same point in the plot when plotting the data.

In CONTROL CHART Required:

on x-axis: milestone date

on y-axis: duration between milestone

point label: Study id

group by different set of control limit (UCL, MEAN, LCL)

for example:

Study Id	Group_By	milestone_date	duration
A01	A	01/20/2011	258
A02	A	01/20/2011	75
A03	A	3/21/2011	128
A03	A	6/18/2011	141
---- - ---	- - - -	- - - - -	-- - - - - -
A01	P	04/20/2011	159
A02	P	05/14/2011	148

How to create control chart for different set of control limit by groupby

required  polt  with symol dot joining by line  with phase reference and phase break

Size of observation range from 0 to max

Which method to choose? is this proc shewhart or other?

I am using SAS 9.2

I tried Proc Shewhart  irchart showing error like unique subgroup, so on

Any help would be gretly appreciated.

Thanks,

rsearch