Like any commodity, the value of the rand is determined by the market forces of supply and demand. Its weakening is also affected by a myriad of structural problems facing the South African economy.
South Africa's current economic situation is reminiscent of events in 1985 when the economy nearly collapsed. This article, first published last year, looks at the similarities.
South Africa has been hit by a severe drought and will not be able to produce enough maize - its staple food - in 2016. This will prompt a rise in imports and therefore food prices.
South African opposition politician Julius Malema has blamed economic policies put in place during Nelson Mandela's era for the country's high levels of inequality. He may have a point.