Looping running sum and total for changing range within grouped variables.

Hi everyone,

I'm relatively new to Stata so please excuse if the explanation of my problem sounds a bit all over the place. I will try my best:

Here is what my data looks like:

Code:

rank	percent	weight
1	1	2000
2	1	3000
3	2	7000
4	2	1200
5	3	3000
6	3	4500

 end

What I want to do is build a loop that for the first group, percent = 1
- generates a variable as the cumulative sum of weight of each observation
- generates a variable as the total sum of weight in that group

And for the second group, percent = 2
- generates a variable as the cumulative sum of each observation from percent = 1 and percent = 2 by the cumulative total of the weights from Perc 1 and 2,
- generates a variable as the total sum of weight from percent = 1 and percent = 2 and so on

In my data the values for percent range from 1-100. However, the loop should only address the first 10 groups, i.e. the first 10 percentile thresholds.

Here is what I tried in Stata, but the results doesn't seem right:

Code:

local k = 1
foreach var of varlist percent_* {
    foreach x in percent_`k' {
        bysort percent_`k' (rank`k'): gen ni_`k' = sum(weight) if `x' == `x'[_n+1]
        bysort percent_`k': egen nall_`k' = total(weight) if `x' == `x'[_n+1]
    }
    local k = `k' + 1
}
end

To give an example of what I'm looking for, eventually it should look like this:

Code:

percent	weight	Ni 1	Nall 1	Ni 2	Nall 2	Ni 3	Nall 3
1	2000	2000	5000	2000	13200	2000	20700
1	3000	5000	5000	5000	13200	5000	20700
2	7000			12000	13200	12000	20700
2	1200			13200	13200	13200	20700
3	3000					16200	20700
3	4500					20700	20700

 end

Any help is much appreciated.

Thank you
Moritz