foreach my $key ( keys %hash ) {

    my @tmp = split /\s+/, $hash{$key};
    my $type = $tmp[0];
    my $dt   = $tmp[1];
    my ($year, $month, $day) = ('','','');
    if($dt =~ m|(\d{4})(\d{2})(\d+{2})T.*$|){
      ($year, $month, $day)=($1,$2,$3);
    }
    ......
    ......
printf("bucket: %s\ttype: %s\t%s-%s-%s\t%s\n",$bucket
+,$type,$year,$month,$day,$dt);
......