Dear Forum,
I have a variable, named "cbo02". I want to calculate the mean of the observations of this variable that are contained in other variable, "t". The "cbo02" variable has 51534752 observations and the "t" variable 132 because "t" is a category and I wanna see which of the "cbo02" observations are contained in "t" and make the mean of it.

cbo02 t
717020 214305
715210 214325
717020 214310
717020 214405
773125 214430
784205 214425
715525 214415
715210 214410
715525 214505
717020 142105
717020 214925
513205 214915
717020 214910
etc...

Thanks.