Display the Savings discount for a product that's on sale on product list pages.

display-savings-discount.php

<?php

/**
 * Display the Savings discount for a product that's on sale on product list pages.
 */
add_action( 'woocommerce_after_shop_loop_item', 'mycode_show_discount_in_product_lists' );
function mycode_show_discount_in_product_lists() {
	global $product; 
	$salediscount = get_post_meta( $product->id, '_dfrps_salediscount', true );
	if ( $salediscount > 0 ) {
		echo '<div class="dfrps_salediscount">';
		echo 'Save ' . $salediscount . '%';
		echo '</div>';
	}
}