Represents an interest rate for a product.

interestRate Object

Property	Data Type (length)	Description
`apr`	decimal	The annual percentage rate of the interest rate
`apy`	decimal	The annual percentage yield of the interest rate
`description`	string	The description of the interest rate
`effectiveDate`	datetime	The date this interest rate was last modified
`expireDate`	datetime	The date the interest rate was altered to expire.
`maximumAmount`	decimal	The maximumAmount required for the interest rate
`minimumAmount`	decimal	The minimumAmount required for the interest rate
`productId`	integer	The Helix-assigned unique ID of the product this interest rate is associated with
`rateEffectiveDate`	datetime	The date the interest rate goes into effect
`rateExpireDate`	datetime	The expire date for the interest rate
`tier`	integer	The tier of this interest rate on a product. Needed to support identifying which interest rate tier a customer account should be associated with