-------------------------------------------------------------------------------- I don't think I understand, but I've never run into a problem that subpop() wouldn't work for, except that Stata is overly conservative regarding estimation with subpops that have single PSUs in a stratum. Bryan Sayer Statistician, SSS Inc. bsayer@s-3.com * * For searches and help try: * http://www.stata.com/support/faqs/res/findit.html * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/