I have around 40 variables in my dataset but I actually only use around 8 of them. I assume that keeping 8 variables is better than keeping all these variables in my dataset, which may cost Stata more time to deal with the data. I am thinking of a good way to deal with that. Can I ask what you should do in this case? Do you create a new panel dataset and run the regression from that or else?

If we just keep some variables in the dataset, whether we can follow this post or is there any simpler way to do so?

Many thanks and warmest regards.

Stata 17, Windows 10.