Be rigid,u r giving information for census is voluntarily its not by force.the safest thing is never open ur door to strangers even like census people.they will not break into ur house.when ur male member of family is at home let him deal with it.be safe.never give anybody chance to annoy u.My rule is NIP THE EVIL IN THE BUD.This is an islamic country and ladies are respected well if they want.Again be rigid,dont open the door before checking for anybody until u r expecting someone.