In what was seen as part of the inexorable shift in viewing habits away from the broadcast networks, a cable TV series has emerged as the top scripted TV show of the past season among the key 18-49 age group for the first time. According to Nielsen Media Research, AMC's The Walking Dead posted an average 7.5 rating for the season among the younger demo, exceeded only by NBC's Sunday Night Football, which averaged an 8.2 in the demo. CBS's The Big Bang Theory ranked third overall with a 7.2 rating. Among total adults, however, CBS's NCIS, which averaged 22.7 million viewers during the season, was the clear ratings winner. By contrast, The Walking Dead drew an average of 12.4 million.