{
	my (%country, %state, %msaname, @msakeys);
	sub do_msalist {
		...
		foreach(sort by_americentric @msakeys) { 
			...
		}
	} #do_msalist

	sub by_americentric {
		$country{$b} cmp $country{$a}
		or
		$state{$a} cmp $state{$b}
		or
		$msaname{$a} cmp $msaname{$b}
		or
		$a <=> $b
	} #by_americentric
}