NBC and ABC continued the wiping process well into the 1970s; while ABC ceased in early 1978, NBC continued to wipe some shows into 1980, leaving much of their daytime game show content lost forever. CBS abandoned the wiping process by September 1972, largely as a result of their collaboration with Goodson-Todman; as a result, even the network's shorter-lived games (such as "Spin-Off" and "Whew!") still exist in their entirety. Incidentally, all three networks ended their wiping practices during the time Fred Silverman led their respective networks.