Re: st: RE: RE: Data management

["Roy,Suryadipta" <suryadipta.roy@lawrence.edu>]

Hi,
 
I am re-typing the question in order to clear up any 
confusion. I am actually trying to generate the last three 
columns (tsum, tshare1, tshare2). Their formulae are given 
below the data:
 
id year	oid    did     dist tvol     tsum tshare1 tshare2
1 2000	1	2	5	1	6	0.17	0.2
1 2000	1	3	10	1	6	0.17	0.2
1 2000	1	4	15	1	6	0.17	0.2
1 2001	1	2	5	2	4	0.5	1
1 2001	1	3	10	2	4	0.5	1
1 2001	1	4	15	2	4	0.5	1
1 2002	1	2	5	3	17	0.18  0.21
1 2002	1	3	10	3	17	0.18  0.21
1 2002	1	4	15	3	17	0.18  0.21
2 2001	2	1	5	2	4	0.5	1
2 2001	2	3	4	2	4	0.5	1
2 2001	2	4	2	2	4	0.5	1
2 2002	2	1	5	4	17	0.24  0.31
2 2002	2	3	4	4	17	0.24  0.31
2 2002	2	4	2	4	17	0.24  0.31
4 2000	4	1	15	5	6	0.83	5
4 2000	4	2	2	5	6	0.83	5
4 2000	4	3	5	5	6	0.83	5
4 2001	4	1	15		4		
4 2001	4	2	2		4		
4 2001	4	3	5		4		
4 2002	4	1	15	10	17	0.59  1.43
4 2002	4	2	2	10	17	0.59  1.43
4 2002	4	3	5	10	17	0.59  1.43

tsum= sum of tvol for all id-s on any particular year;
tshare1= tvol/tsum;
tshare2=tvol/(tsum-tvol).

Thanks again for all your help (and sorry for the typos 
before).

Suryadipta.
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