China's central bank has set the value of the yuan at the currency's lowest level against the U.S. dollar in eight years.

The "parity rate" for the yuan, also known as the "renminbi," or people's money was 6.9168 on Friday, its lowest level since 2008. It was at 6.9184 by midday.

The U.S. dollar has surged against other currencies since Donald Trump won the Nov. 8 presidential election.

Trump has threatened to seek to penalize China and Japan for manipulating their currencies to gain a foreign exchange advantage for their exporters.

China's Foreign Exchange Trading System allows the yuan to rise or fall a maximum of 2 percent against its parity rate, which is based on a weighted average of prices offered by market makers before trading starts each day.