Supergirl kicked off its third season this week, though it did so with nearly less than half of its Season 2 premiere audience.

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Supergirl's Season 3 debut averaged a 0.5 rating in adults 18-49 and 1.9 million total viewers in its 8 PM Monday slot -- a drop off of nearly fifty-percent in the 18-49 demographic and nearly forty-percent in live viewers from the show's Season 2 premiere.

That's a pretty large drop for a series that was at one point averaging around six million live viewers during its first season on CBS. However, it is worth noting that unlike other networks, a huge drop off like this isn't necessarily cause for concern on the CW. Take Arrow, for example, a series that The CW continues to renew despite ratings that fell below two million live viewers in its fifth season. Live viewers are important, yes, but its the Live +7 day numbers that matter the most, and CW shows tend to do well in that area.

With that said, these aren't the episode's final ratings -- expect Supergirl's numbers to tick when the Live +3 ratings and Live +7 ratings are released.

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Airing on The CW on Mondays at 8 p.m. ET/PT, Supergirl stars Melissa Benoist in the title role, David Harewood as Martian Manhunter, Mehcad Brooks as Jimmy Olsen, Chyler Leigh as Alex Danvers and Jeremy Jordan as Winn Schott, with appearances by Calista Flockhart as Cat Grant and Tyler Hoechlin as Superman.