In recent years businesses in the United States are becoming more diverse places in which to work. Workforce diversity with respect to race, gender, and ethnicity has increased as result of socio-cultural changes, and is to some extent protected by law. While demographic diversity in American businesses has become more apparent, a range of individual differences in the values, attitudes, beliefs, and personalities of their employees is assumed to have existed for some time. However Benjamin Schneider, a psychology professor at the University of Maryland, argues that the range of individual differences in the above mentioned psychological variables becomes less common within businesses over time.