Please help me identify cause of Google referrer traffic drop

[infauPaul]

[i.imgur.com ]

The chart above shows traffic from Google / Organic.

As you can see, traffic from Google is down about 60% around October 27. I can think of 3 possible causes; I need your help to identify which one.

1. Latest Google Panda update. But significant traffic drop occurs almost one month after Google Panda roll out. So I doubt it.

2. Latest Google Penguin update. But my website has only a few inbound links, which grow organically. I promote content exclusively on Twitter. So I think this is the least likely cause.

3. Content optimization I implemented on October 20. I thought this was the most likely cause. So I reverted the update on October 27. Still, I don't see any traffic improvement since then.

What do you think is the most likely cause? Thank you.

[Planet13]

What type of content optimization did you do?

[infauPaul]

Please don't judge me, but I am not good at writing "quality" content, and my website's business model is "thin content" for niche markets. I have been running it for five years. So previous Panda updates would have already affected it. More importantly, the rollout period of Panda 4.1 doesn't make the day when my Google traffic suddenly dropped. However, it is still possible that Panda 4.1 may take one month to roll out, instead of one week believed by most people. That's why I am asking here.

What I did to "optimize" my content is to add related content immediately after the main post. So together they appear like a single article. Google may treat this as duplicated content. As previously said, I reverted the "optimization" after one week when I noted sudden traffic drop.

My question is 1) if this is caused by Panda 4.1; 2) if not, when the traffic would return to normal. Thanks.

[anim8tr]

I wouldn't spend too much time worrying about the timing of Google updates in relation to your traffic. You should be focusing on creating better content like Google has strongly recommended for at least a couple of years. If you can't write better content, then try to find someone who can. If you can't do this, then I'd suggest you find a different source of income because it looks like Google has your number and the gig is up.