how to determine the 3-digit SIC code for industry ?

[Mareah]

Hi

I'm doing a panel data analyses and I want to control industry effect using industry dummy variable.
to do so, I need to determine two-digit or three-digit SIC code. [as in some articles]
however, the ID number for industries are various with 2, 3, and 4 digit.
[e.g. 21100, 4643, 791 etc]

so how can I convert these different number of digits into only 2 or 3 digit ?

Thanks

[Lazar]

Take the first two digits. I believe SIC and SOC codes are the same as ISSCO-88 and thus this should be fine.

[Mareah]

Hi

Thanks for your replay.
I handle this using excel. so I prepare the dataset before imputed in stata