Add save amount next to sale item prices

gistfile1.txt

// Add save amount next to sale item prices
add_filter( 'woocommerce_get_price_html', 'modify_woocommerce_get_price_html', 10, 2 );
function modify_woocommerce_get_price_html( $price, $product ) {
    if( $product->is_on_sale() && ! is_admin() )
        return $price . sprintf( __('<p class="saveprice">Du sparar: <span class="woocommerce-Price-amount amount">%s <span class="woocommerce-Price-currencySymbol">kr</span></span></p>', 'woocommerce' ), $product->regular_price - $product->sale_price );
    else
        return $price;
}