while ( my $line = <DATA> ) {
    next unless $line =~ /\d{4,}\.\d{3}-\d{4,}\.\d{3}/;
    my( $bytes ) = $line =~ /\s(\d+)$/;
    if ( $bytes > $grenzwert ) { $data .= '1' }
    else                       { $data .= '0' }
}