Hi,

I've dataset like this:
Code:
* Example generated by -dataex-. To install: ssc install dataex
clear
input float(id credit time)
12 1100 1101
12 1200 1102
13 1800 1303
13 475 1304
13 980 1305
13 600 1306
15 325 1201
15 478 1202
15 645 1203
15 741 1204
end
which two first 2 numbers of time are year(12=2012) and the second two numbers are month(01=jan)
I want to merge each two rows into one, something like this:

id credit time
12 (1100+1200=1300) 1101
13 (1800+475) 1303
13 (980+600) 1305
15 (325+478) 1201
15 (645+741) 1203

where actually 1100+1200 will replace with 1300
actually results observations will be half of the primary observations.


thanks a lot