TVNZ said that its daily soap opera Shortland Street and Agent Anna had worked well, but New Zealand On Air is concerned about the challenges facing dramas.
The number of people using televisions (know as 'PUTs' in the ratings terms) was down in October, and beyond that dramas have faced trouble maintaining audience loyalty.
South Pacific Pictures chairman John Barnett - a key figure in the development of New Zealand TV drama - said that there were new challenges, including different ways in the way that people watched shows.
Increasingly overnight ratings did not represent viewers who watched outside scheduled times, viewing shows on-demand or on personal video recorders such as MySky.
In particular PVR's had increased the level of "binge viewing" where people recorded three of four episodes and watched them in a single block.
New Zealand On Air televsision manager Glenn Usmar said that it was examining this and other drama viewing trends which were part of an international trend and NZ On Air will talking to TVNZ and TV3 about the way ahead.