Historically, African-American businesses have been restricted to the narrow range of service enterprises. African Americans have tended to establish businesses that require relatively limited capital and technical expertise, such as personal services and small-scale retailing. These firms have had to rely heavily on the African-American community as their market for goods and services. In 2002 four out of ten black-owned firms provided health care and social assistance, personal services, and repair and maintenance. These services remain a key base for African-American businesses.