st: Dropping variables with mostly missing values again

["Eric M. Uslaner" <euslaner@umd.edu>]

Thanks to Rich, Amirsa, Jeph, and Nick.  It is likely my ignorance but I can't get this resolved.  For the solutions of Rich, Amirsa, and Jeph, I get all missing values.  For Nick's suggestion, I have:

foreach V of varlist elecprod1750-visitorrooms2003 {
	npresent,min(20)
	keep `r(`V')' 
}   

And I see the npresent results as he suggested.  But the do file  I constructed above after the last variable leads to:

varlist or in range required
r(100);

end of do-file

r(100);

And no values are changed.  What, please, am I doing wrong?  Thanks.

Ric


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