The monthly rent deduction requirement refers to the monthly rent paid for the purpose of leasing a residential property. In this case, the monthly rent amount is calculated by dividing the total amount of rent to be paid during the lease period as specified in the lease agreement by the number of days in the lease period for the residential property and then multiplying it by the number of days of occupancy within the taxable period. In the given scenario, the deductible monthly rent amount would be the full amount for all 12 months.