A graduated payment mortgage (GPM) starts with an initial low monthly payment to help low-income homeowners. This payment amount increases over time. This is a beneficial way to help sub-prime mortgage seekers and young people with home ownership. The problem with the GPM is that its success depends upon future earnings potential. Each year, the monthly payments increase by a pre-set percentage. In good economic times, young people can advance their careers and increase their salary. These higher paychecks enable homeowners to keep up with the mortgage payment increases. This is an example of a negative amortization loan. The overall expense of a GPM is higher than conventional mortgages. A variety of repayment period schedules are available. This is a more attractive loan during times of economic growth, when employment numbers and salaries are increasing; however, it is more risky during economic downturns.