Hi

I have kind of data as follows. I want to create a graph
of the total number of login - logout vs. time elapse.

That is I want to create another two columns. One to
count the number of logins and another to count the
number of logouts.

I only have the data in the first column. What is the
function to create the second column, No.of Logins?

No.of Logins No.of Logout No.ActiveUsers
Login 1 0 1
Login 2 0 2
Logout 3 1 2
Logout 3 2 1
Login 4 2 2
Logout 4 3 1
Login 5 3 2
....

Thanks,
Jirong