I always have 12 $new['period_??']. For now, I write these code 12 times after I declare a $new['period_??']. Is there any way to make it simpler?

foreach ($new['period_10'] as $item) {
    $po_10th[] = $item->po_id;
}
$new['uni_10'] = array_unique($po_10th);
foreach ($new['uni_10'] as $po_id) {
    $po = $this->model_prcsys->get_po_by_id(md5($po_id));
    $pos_10[] = $po['po_id'];
    $currency10[] = $po['currency'];
}
$cur_pos_10 = array_unique($currency10);
foreach ($cur_pos_10 as $currency) {
    $new['po_arr_10'] = $this->model_prcsys->get_pos_with_curr($pos_10, $currency);
    $total_price = array();
    $curren = array();
    foreach ($new['po_arr_10'] as $key) {
        $total_price[] = $key->total_line_price;
        $curren[] = $key->currency;
    }
    $new['total_n_curr10'][] = array_merge(array(array_sum($total_price)), array_unique($curren));
}

This is the hard reality I've been done!

$new['period_1'] = $periodic_items[0];
$new['frek_1'] = $frek[0];
$new['period_2'] = $periodic_items[1];
$new['frek_2'] = $frek[1];
$new['period_3'] = $periodic_items[2];
$new['frek_3'] = $frek[2];
$new['period_4'] = $periodic_items[3];
$new['frek_4'] = $frek[3];
$new['period_5'] = $periodic_items[4];
$new['frek_5'] = $frek[4];
$new['period_6'] = $periodic_items[5];
$new['frek_6'] = $frek[5];
$new['period_7'] = $periodic_items[6];
$new['frek_7'] = $frek[6];
$new['period_8'] = $periodic_items[7];
$new['frek_8'] = $frek [7];
$new['period_9'] = $periodic_items[8];
$new['frek_9'] = $frek[8];
$new['period_10'] = $periodic_items[9];
$new['frek_10'] = $frek[9];
foreach ($new['period_10'] as $item) {
    $po_10th[] = $item->po_id;
}
$new ['uni_10'] = array_unique($po_10th);
foreach ($new['uni_10'] as $po_id) {
    $po = $this->model_prcsys->get_po_by_id(md5($po_id));
    $pos_10[] = $po['po_id'];
    $currency10[] = $po['currency'];
}
$cur_pos_10 = array_unique($currency10);
foreach ($cur_pos_10 as $currency) {
    $new['po_arr_10'] = $this->model_prcsys->get_pos_with_curr ($pos_10, $currency);
    $total_price = array();
    $curren = array();
    foreach ($new['po_arr_10'] as $key) {
        $total_price[] = $key->total_line_price;
        $curren[] = $key->currency;
    }
    $new['total_n_curr10'][] = array_merge(array(array_sum($total_price)), array_unique($curren));
}

$new['period_11'] = $periodic_items[10];
$new['frek_11'] = $frek[10];
$new['period_12'] = $periodic_items[11];
$new['frek_12'] = $frek[11];

Can anyone help me make it simpler? It always loops 12 times.