How to make a negative number in excel as a number. Here is my code MagentoFrameworkAppResponseHttpFileFactory $fileFactory, $content[] = [ 'qty' => __("QTY"), 'part_number' => __("PART NUMBER"), 'invoice' => __("INVOICE #"), 'date' => __("DATE"), 'description' => __("Description"), 'retail' => __("RETAIL"), 'd_discount' => __("DEALER DISCOUNT"), 'a_discount' => __("ADDITIONAL DISCOUNT"), 'total' => […]