'Downton Abbey' Season 2 Finale Marks PBS' Highest-Rated Program Since 2009

The zeitgeist-ing "Masterpiece Classic" drama pulled in an average 5.4 million viewers, the best performance since the bow of Ken Burns' "National Parks."

British period drama Downton Abbey concluded its stateside sophomore run on Sunday night. And after seeing gains across the board all season long, it ended on a particularly high note.

Fast National ratings give the Masterpiece Classic broadcast of the Season 2 finale 5.4 million viewers. Not only does that mark a nearly 30 percent increase from the 4.2-million-strong season premiere, it doesn't even include DVR, online streaming or station replays. Those Live + 7 day ratings have driven previous Abbey outings up by 50 percent.

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The finale marks PBS' highest overnight rating in over two years, making it the strongest program for PBS since Ken Burns' National Parks premiered in Sept., 2009.

“PBS and our member stations are so pleased that such a large audience is enjoying this great work from Masterpiece,” said PBS president and CEO Paula Kerger. “From viewing parties to Twitter mentions, Downton Abbey is riding a wave of public enthusiasm, and it’s been wonderful to see so many people discovering public television as a destination for programming that’s smart, distinctive and entertaining.”

Kerger recently spoke to The Hollywood Reporter about Downton Abbey and her surprise over the series' incredibly strong performance.

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"Anyone who tells you that they knew something was going to be a smash is obviously blowing smoke," she said. "You think you're picking well, but when something really pops, it's a combination of good content and hitting at the right time."

Metered market averages give this current run of Downton Abbey a 25 percent uptick, overall, from the Season 1 run in 2011. And the growth has extended online. Thus far, full episodes of the second season have brought in 4.8 million views to the PBS video portal -- a 400 percent jump, season over season. It's also given the Masterpiece site its highest traffic ever throughout the current season.