Randomly cutting observations from dataset

[sofia sia]

I am using a dataset with over 60,000,000 observations -- how can I randomly cut observations to roughly 1/4 of this amount? Is there a relatively straightforward STATA command for this?

[George Ford]

drop if r(uniform) < 0.75

[Felix Bittmann]

As an addition to George's helpful response: if you want to make this process reproducible (which you probably should), you can extend the command to:

set seed 123
drop if r(uniform) < 0.75

[Andrew Musau]

The random number function is -runiform()-

help runiform()