20. The rent payable by a lessee who applies for a rent reduction because of a decrease in income or a change in the composition of the household shall be determined on the basis of the presumed income of all the occupants for the period for which the reduction is granted.
In all cases, basic rent may not be less than the minimum basic rent determined in accordance with the provisions of section 8, which is based on the presumed household situation for the period for which the reduction is granted.
An application for a rent reduction shall be accompanied with all the necessary supporting documents.
No application for a monthly rent reduction of less than $10.00 may be granted.
The lessor shall inform the lessee of his decision within 30 days of the date on which the application and the supporting documents were filed.