The autumn period will be particularly crucial for ITV, which has seen dramatic falls in its share of commercial impacts across all audiences.
Battered by the BBC's coverage of the Olympics, in August it received its lowest- ever audience share. With the absence of the Rugby World Cup from this autumn's schedule, few expect it to make up the ground it has already lost.
However, its debut Parkinson programme brought in 5.7 million viewers.
The rival channel five has also suffered declines across many of its audiences. According to Barb data for the year to the end of August, its shares of commercial impacts for its key trading audiences of housewives with children and young adults have fallen by 7.9 per cent and 3.6 per cent respectively.
Of all the terrestrials, only Channel 4 has had a good year, with audiences up across the board - its shares of both young adults and upmarket adults have increased by more than 5 per cent. Based on these results, Channel 4 can expect to see a significant increase in its share of TV ad revenue come the negotiation season.
Andy Zonfrillo, the broadcast director at MindShare, said: "Channel 4 has already had a strong year and with The Simpsons due to start in November, will also have a strong finish to the year.
"However, ITV1 will not make up the ground that it lost earlier in the year - the network will now try to limit its losses.
"Five has had an average year and its audience is becoming older and more upmarket."