for most of the 19th and 20th centuries, the united kingdom largely used the long scale, whereas the united states used the short scale, so that the two systems were often referred to as "british" and "american" in the english language. after several decades of increasing informal british usage of the short scale, in 1974 the government of the uk adopted it, and it is used for all official purposes. with very few exceptions, the british usage and american usage are now the same.