Missouri changed its refund rate from 0.6% to 0.4% effective October 1, 2021. This change was already included in the 21.3.0.0 version of Instant Interest.

Two states announced plans to change their interest rates for both underpayments and overpayments effective January 1, 2022:

• Iowa will change from 6.0% to 5.0%.
• Indiana will change from 4.0% to 3.0%.

Both of these changes are reflected in this release.