use strict;
use warnings;
use XML::Twig;

my $t= XML::Twig->new (twig_roots => {'Data' => \&extract});
$t->parse (do {local $/; (<DATA>)});


sub extract 
{
my ($t, $data) = @_;
$data->print;
print "\n";
}

__DATA__
<Row AutoFitHeight="0">
<Cell><Data ss:Type="String">DATA1</Data></Cell>
<Cell><Data ss:Type="String">DATA2</Data></Cell>
<Cell><Data ss:Type="String">DATA3</Data></Cell>
<Cell><Data ss:Type="String">DATA4</Data></Cell>
<Cell><Data ss:Type="String">DATA5</Data></Cell>
<Cell><Data ss:Type="String">DATA6</Data></Cell>
<Cell><Data ss:Type="String">DATA6</Data></Cell>
<Cell><Data ss:Type="String">DATA7</Data></Cell>
</Row>