You have

the following code:

return order.quantity * order.itemPrice -
      Math.max(0, order.quantity - 500) *
      order.itemPrice * 0.05 +
      Math.min(order.quantity * order.itemPrice * 0.1, 100);

const basePrice = order.quantity * order.itemPrice;
const quantityDiscount = Math.max(0, order.quantity - 500) * order.itemPrice * 0.05;
const shipping = Math.min(basePrice * 0.1, 100);
return basePrice - quantityDiscount + shipping;

What type of refactoring is this?