(1) This section applies if:
(a) the Commissioner makes a determination under section 19 that an underpaid amount is to be paid in respect of a person for an income year; and
(b) the determination is made on the basis that a particular amount is the correct amount of the Government co - contribution payable in respect of the person for the income year; and
(c) the determination is necessary to correct an administrative error.
(2) The payment shortfall is the difference between:
(a) the amount referred to in paragraph ( 1)(b); and
(b) the sum of the amounts that have already been paid by way of Government co - contribution in respect of the person for the income year before the determination under section 19 is made .
(3) The amount of the Government co - contribution in respect of the person for the income year is increased by the amount of interest worked out under subsection ( 4).
(4) The interest is to be calculated:
(a) on the amount of the payment shortfall; and
(b) for the period from the payment date for the Government co - contribution (see subsection 17(2)) until the payment date for the underpaid amount (see subsection 21(2)); and
(c) on a daily basis; and
(d) at the base interest rate for the day on which the interest is calculated.
(5) The regulations:
(a) may provide that an error of a kind specified in the regulations is an administrative error for the purposes of this section; and
(b) may provide that an error of a kind specified in the regulations is not an administrative error for the purposes of this section.