BEGIN {
	FS = "	";
}

{
	pop[$4] += $3;
}

END {
	for (c in pop)
		printf ("%15s	%6d\n",c,pop[c]) | "sort -t'	' +1rn";
	close ("sort -t'	' +1rn");
	sleep (1);
}
           Asia	  2173
  North America	   340
         Europe	   172
  South America	   134