Timechart for unique login ids

[freephoneid]

I've following data in my summary index by time which runs in time range -1d@d to @d every day @ midnight:

09-01-11: userid=1, userid=2, userid=5
09-02-11: userid=2, userid=7, userid=11
09-03-11: userid=1, userid=9, userid=2, userid=33
09-04-11: userid=15, userid=1, userid=11, userid=33
09-05-11: userid=2, userid=9, uesrid=11
09-06-11: userid=50

In above case, I want to show the time chart as shown below:

09-01-11: count=3
09-02-11: count=2 (Since userid=2 is already counted earlier)
09-03-11: count=2 (Since userid=1 & userid=2 is already counted earlier)
09-04-11: count=1 (since userid=1, userid=11, userid=33 are already counted earlier)
09-05-11: count=0 (since userid=2, userid=9, uesrid=11 are already counted earlier)
09-06-11: count=1

How can I display timechart which will show unique userid count over time?

Thanks

[freephoneid]

Hello Experts,

I'm sure this can be done in Splunk but still trying to figure out how to do calculations with time chart...

Please note that the userid=12 are different log lines. So, in my summary index, they're actually represented as shown below:

09-01-11: userid=1
          userid=2
          userid=5
09-02-11: userid=2
          userid=7
          userid=11
09-03-11: userid=1
          userid=9
          userid=2
          userid=33

Basically, I've simply added these log lines containing userid key/value pair in the summary index for each day.

I'll appreciate if you can post the splunk query to display the timechart.

Thanks!