A Certain Ratio (aka ACR or A.C.R.) are a post-punk/funk band from Manchester, UK. Formed in the late 1970s, they were one of the bands (along with Gang Of Four and The Pop Group) who forged the new musical hybrid which became known as punk-funk, a style which fused the energy and aggression of punk rock with the rhythms and musicianship of funk and soul. The band’s members were originally Simon Topping, Jeremy Kerr, Martin Moscrop, Donald Johnson and Pete Terrell. In live performance, the band often had a flexible line-up, with various members swapping instruments, and also performing ensemble latin percussion music.