If the user specifies ChargeAmountForEachAdditionalItem for FlatShippingRateOption, then this value is used to specify how much to charge for each additional item.
See the Field Index to learn which calls use AmountPerAdditionalItem.
If the user specifies DeductAmountFromEachAdditionalItem for FlatShippingRateOption, then this value is used to specify how much to deduct for each additional item shipped.
See the Field Index to learn which calls use DeductionAmountPerAdditionalItem.
For the given range, specifies the cost of insurance. If the InsuranceOption is either Optional or Required, then 6 instances of this field must be specified, one for each cost range.
See the Field Index to learn which calls use FlatRateInsuranceRangeCost.