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You're very welcome. OK, so if we can see that the drop happened May 20, 2014, then there is a high possibility that Panda has affected your site. We can't always say that with certainty though. I remember the week following that date, I had three separate sites that came to me saying that they had been horribly hit by Panda. One of the sites had done a redesign and launched May 19. The redesign changed all of the title tags and the urls, so it was not Panda's fault that they dropped in rankings. Another site had also redesigned and the developer forgot to put the Google analytics tracking code on the site. So, rankings didn't change but it looked like traffic plummeted. And the final site had accidentally noindexed 90% of their site. I'm not kidding! Still, a big drop on May 20 (give or take one day) means that there are on-site quality issues to address. While it's never wrong to audit your backlinks I'd spend more time reviewing on page factors. When Panda first came out I spent a lot of time looking at thin and duplicate content. While that stuff, especially thin content is still important, there are a LOT more factors that go into Panda. I firmly believe now that Panda is Google's way of figuring out what users prefer seeing. As such, I focus on three things: Improving technical SEO. Removing or vastly improving thin content. (And yes, redirecting to an appropriate page or category page is fine.) Figuring out how the site can be the best of its kind for users. This involves looking at competitors' sites with a non-biased eye and also looking at analytics data to see if there are pages in the index that users are not happy with (i.e. they consistently bounce or spend very little time on the page compared to others.) Here is more on my approach to Panda: https://moz.com/blog/have-we-been-wrong-about-panda-all-along Best of luck! Marie