British standard BS 1380:1947 adopted the fractional gradient criterion of the American 1943 standard, and also included arithmetic speed numbers in addition to logarithmic numbers. The logarithmic speed number proposed in the later BS 1380:1957 standard was almost identical to the DIN 4512:1957 standard, except that the BS number was +9 degrees greater than the corresponding DIN number; in 1971, the BS and DIN standards changed this to +10 degrees.