In R9 Districts and in M1 Districts paired with an R9 District, for zoning lots with a minimum lot area of 40,000 square feet or more, for each square foot of publicly accessible, supplemental open area provided in accordance with Section 117-365 (Requirements for supplemental open spaces and amenities), inclusive, the maximum floor area permitted on the zoning lot may be increased by six square feet, provided that the resulting bonus floor area ratio shall not exceed 0.6.