The Commission shall annually assess against all licensed insurance companies doing business in this Commonwealth by writing any type of flood insurance an assessment in the amount of one percent of the total direct gross premium income for such insurance. Such assessment shall be apportioned, assessed, and paid as prescribed by § 38.2-403. In any year in which a company has no direct gross premium income from flood insurance or in which its direct gross premium income from flood insurance is insufficient to produce at the rate of assessment prescribed by law an amount equal to or in excess of $100, there shall be so apportioned and assessed against such company a contribution of $100. One hundred percent of the total amount collected annually pursuant to this section shall be paid into the Dam Safety, Flood Prevention and Protection Assistance Fund established per § 10.1-603.17. The assessment established by this section shall not apply to premium income for policies written pursuant to the National Flood Insurance Act of 1968 or for policies providing comprehensive motor vehicle insurance coverage.