The territory of Northern Rhodesia was administered by the South Africa Company from 1891 until takeover by the UK in 1923. During the 1920s and 1930s, advances in mining spurred development and immigration. The name was changed to Zambia upon independence in 1964. In the 1980s and 1990s, declining copper prices and a prolonged drought hurt the economy. Elections in 1991 brought an end to the one-party rule of Kenneth Kaunda, but the subsequent vote in 1996 saw blatant harassment of opposition parties.