Use Woo Admin Reports

gistfile1.txt

include_once(ABSPATH . 'wp-content/plugins/woocommerce/includes/admin/reports/class-wc-admin-report.php');
 
$report = new WC_Admin_Report();
 
$start_date = get_field('campaign_start_date', $campaign->ID);
$end_date = get_field('campaign_end_date', $campaign->ID);
 
$report->start_date = strtotime($start_date);
$report->end_date = strtotime($end_date);
 
$args = array(
    'data' => array(
        '_order_total' => array(
            'type' => 'meta',
            'function' => 'SUM',
            'name' => 'total_sales'
        )
    ),
    // add filter to return results containing a particular meta key/value
    'where_meta' => array(
        array(
            'meta_key' => 'cause',
            'meta_value' => $post->ID,
            'operator' => '='
        )
    ),
    'filter_range' => true,
    'debug' => false
);
 
$order_totals = $report->get_order_report_data( $args );