Audiences take a dive for Coro St and MasterChef

Michelle Keegan who plays Tina McIntyre in Coronation Street. Photo / Supplied

TVNZ's controversial swap between Coronation Street and MasterChef Australia has dealt both slots a hammering in the ratings.

Figures show TVNZ lost around 40,000 viewers for both programmes in the key 25-54 demographic.

At 5.30pm, an average of 65,880 viewers tuned in to watch Coronation Street this week, compared with the audience of 79,148 who watched MasterChef Australia the previous week.

In the primetime 7.30pm slot, an average of just 118,950 viewers tuned in to MasterChef Australia compared with the 145,485 who had been watching Coronation Street.

Over on TV3, Home and Away and The X Factor USA had made encouraging gains, according to a spokeswoman.

TVNZ spokeswoman Georgie Hills said one week was too short a time to judge the ratings. No decision had been made about whether the Coronation Street shift would be permanent, she said.

"We have always said we want to wait and see how the rescheduled shows perform before we make a final decision about any long-term changes."