Students' rate of return on their large investment in time and money depends to a great extent on their study area. A longitudinal study by the Department of Education and Training found that median full-time salaries for undergraduates four years into their careers ranged from $55,000 in the creative arts to $120,000 in dentistry. For those with a master's degree or higher, the figures range from $68,800 in communication studies to $122,100 in medicine. Rates of graduate unemployment and underemployment also vary widely between study areas. For comparison, the average taxable income for the top ten trades range from $68,000 for landscapers to $109,000 for boilermakers.