st: Calculating a (changing) accumulative sum

[oezguer.guererk@uni-erfurt.de]

I have 20 "period"s (i.e., 20 rows) of data for each "subject" i. For 
each subject i, I would like stata to calculate the accumulative sum of 
the variable "con" in a new variable "accumcon" in the following way:

In period 1: accumcon = con[1]. In period 2:  accumcon = con[1]+con[2] 
In period 3: accumcon = con[1]+con[2]+con[3] and so on, for each 
subject, from period 1 until period 20.

Thank you for your help.

--
Dr. Özgür Gürerk

Lehrstuhl für Mikroökonomie & Laboratorium für experimentelle Wirtschaftsforschung
(Microeconomics & Laboratory for Experimental Economics)

Universität Erfurt, Nordhäuser Str. 63, D-99089 Erfurt 

Tel: +49 361 7374561
Fax: +49 361 7374569
www.uni-erfurt.de/elab
--

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