# Setting transaction types to block accrual charges

You can specify that certain transaction types block accruals if they are the only transaction types on the cardholder’s statement. This helps to reduce delinquency, since if these types of transactions are the only transactions at the end of the cycle, no value for the account's [open\_due\_date](https://developers.pismo.io/pismo-docs/docs/setup-overview#account)  field is set, and the account as a whole does not accrue charges.

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> An account also does not accrue charges if the unpaid balance is less than the minimum amount defined for the program. See [Calculating interest accruals](https://developers.pismo.io/pismo-docs/docs/calculating-interest-accruals) for more information.

Use the program parameter `IGNORE_ACCRUALS_IF_ONLY_TTS` to specify which transactions should not accrue charges if they are the only transactions on the statement. This parameter takes an array of their transaction type IDs.You set this with the [Update multivalue program parameter values](https://developers.pismo.io/pismo-docs/reference/updateprogramparamenter) endpoint. Look up the parameter ID for `IGNORE_ACCRUALS_IF_ONLY_TTS` in the [Multivalue program parameters guide,](https://developers.pismo.io/pismo-docs/docs/multivalue-parameters) Set `parameterID` to this value, and use the`values` field to set the transaction type IDs.

For example, suppose the parameter ID of the annuity transaction type is 5, and you set `IGNORE_ACCRUALS_IF_ONLY_TTS` to an array containing only the number 5. Then, if only annuity transactions exist at the end of a cycle, the account is marked to not calculate accruals on the next cycle. However, if any other type of transaction is posted on the statement, then charges do accrue, even on the annuity transactions.

Use the following endpoints to retrieve a list of the configured transaction types or to delete the list, respectively:

* [Get program parameter values](https://developers.pismo.io/pismo-docs/reference/getprogramparameter)
* [Delete program parameter values](https://developers.pismo.io/pismo-docs/reference/deleteprogramparamenter)