It was created by Ian Witten, Tim Bell and John Cleary from the University of Calgary in 1987 and was commonly used in the 1990s.
Results were most commonly listed in bits per byte (bpb) for each file and then summarized by averaging.
This method was used in a benchmark in the online book Data Compression Explained by Matt Mahoney.
According to the rules of the contest, an entry must consist of both the compressed data and the decompression program packed into one of several standard archive formats.
Currently the program must run within 24 hours on a 2000 MIPS machine under Windows or Linux and use less than 800 MB memory.
The first entry received was 759,881 bytes in September, 1997 by Malcolm Taylor, author of RK and WinRK.