Numbers were down, again, for “opening night” on “American Idol.”

Tuesday night, when the 12 finalists sang, averaged 23 million viewers — down from 25 million for the same show last year and 30 million in 2008.

While those are still terrific numbers for TV’s top-rated show, it continues a downward trend for the first night showcasing the 12 finalists.

“Idol” is under more scrutiny this season, with new judge Ellen DeGeneres — and Simon Cowell leaving after this season.