The NHS spends approximately £9 billion a year on branded prescription medicines. The Pharmaceutical Price Regulation Scheme (PPRS) controls their prices by regulating the profits that companies can make on these sales. It is not a conventional market with a single purchaser (the government) and manufacturers, which hold patents that provide temporary monopolies over supply of their products. A new PPRS was implemented from 1st January 2009, including, amongst other things, provision for a second cut in the price of branded medicines from 1st January 2010. In the absence of statutory fall-back measures, companies could avoid that price cut by choosing not to join the voluntary scheme.