Western German students have more money at their disposal than their eastern German counterparts, a study by the Deutsches Studentenwerk found out. In 2003, the financial situation among German students varied from an average income of €651 ($849) in Thuringia to €858 in Hamburg, while the overall federal average came to €767 per month. In all western German states, except for Lower Saxony and Baden-Württemberg, the average student income exceeds the federal average. In addition, the study on the living condition of students in Germany, which is conducted every three years, shows that female students are generally worse off financially. On average, they earn one euro less per hour than their male counterparts. Meanwhile, Klaus Zimmermann, head of the German Institute for Economic Research, expects university tuition fees to rise to €2,500 per semester on average within the next five years.