The overnight ratings for Saturday's final earned just over half the 13.1 million viewers who tuned in for the "Britain's Got Talent" final in May, the BBC reported Sunday.
That makes "The Voice" the highest-rating debut for a BBC program on record, said a BBC spokeswoman, whose name was not reported.
Ratings peaked earlier in the season at more than 10 million viewers, but had dropped to 4.5 million by last week, BBC reported.
BBC One controller Danny Cohen said producers will look for ways to improve the series in the future.
"We'll take away a few things from the live shows to tinker with for series two," he said.
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