For purposes of this subpart, we will consider a reduction in your income to be significant if your modified adjusted gross income decreases; and

(a) The decrease reduces the percentage of the income-related monthly adjustment amount you must pay according to the Table of Applicable Percentages in §418.1120; or

(b) The decrease reduces your modified adjusted gross income to an amount below the threshold described in §418.1105 and eliminates any income-related monthly adjustment amount you must pay.