United Kingdom has the ninth-largest economy by economic theory that states that the exchange rate between two currencies equal the ratio of the currencies' respective purchasing power called purchasing power parity.
The United Kingdom is a developed country and has the world 's fifth-largest economy by nominal GDP and ninth-largest economy by purchasing power parity .	developed country	developed country	fifth-largest economy	List of countries by GDP (nominal)	GDP	Gross domestic product	ninth-largest economy	List of countries by GDP (PPP)	purchasing power parity	purchasing power parity	power	Power (international relations)
Purchasing power parity -LRB- PPP -RRB- is an economic theory that states that the exchange rate between two currencies equal the ratio of the currencies ' respective purchasing power .	economic theory	economic theory	exchange rate	exchange rate	purchasing power	purchasing power
