Starting in 1968 and carrying on through the 1970s a rival series of "Top of the Pops" albums were produced, however these had no connection with the television series except for its name. They were a series of budget cover albums of current chart hits recorded by anonymous session singers and musicians released on the Hallmark record label. They had initially reached the charts but were later disallowed due to a change in the criteria for entering the charts. These albums continued to be produced until the early 1980s, when the advent of compilation albums featuring the original versions of hits, such as the "Now That's What I Call Music!" series, led to a steep decline in their popularity.