Can someone explain this chart of mining pools?

[Bizmark13]

I found this screenshot of a website on my hard drive and I'm not sure where I got it from or what it's exactly meant to represent. I tried Blockchain.info and Bitcoincharts.com but neither of them seem to be the website that houses the chart in my picture. As for the chart itself, well it seems to show the hashrate of the popular Bitcoin mining pools in GH/s.

There are a few problems though. First of all, where is GHash.IO? Secondly, why do the hashrates of BTCGuild and Eligius suddenly nosedive in a vertical line? Did something bad happen to them? And if so, why didn't the hashrates of the other pools increase to accommodate these miners?

[eleuthria]

There are a few problems though. First of all, where is GHash.IO? Secondly, why do the hashrates of BTCGuild and Eligius suddenly nosedive in a vertical line? Did something bad happen to them? And if so, why didn't the hashrates of the other pools increase to accommodate these miners?

Because the graph is inaccurate, simple as that.  There was never a nosedive in hashrate of BTC Guild or Eligius, so the graph is clearly being built off of inaccurate data.

[kano]

Explanation: it's a year old

[eleuthria]

Explanation: it's a year old

*AND* broken/inaccurate even for a year ago.  Eligius/Guild never had a dive like that, and Slush hasn't been bigger than BTC Guild since 2011 yet the chart shows Slush on top at the end of it with Guild & Eligius not even visible.

[fresca]

Explanation: it's a year old

Things sure move fast in the bitcoin world!

[cyberpinoy]

A lot of things could have happened to show those nose dives, maybe this shot was taken during a time of some pool hopping, and that was when all the people hopped out of those 2 pools and into another one, maybe a lot of members got pissed and just left those 2 pools. Ghash not being there couls be because it was filtered out.

As far as where it came from who knows. there is a multitude of info all over the net, some good some bad some true some false so who knows where ti came from. If you didnt change the pics name and it was downloaded from the net directly try googling the image name.

[os2sam]

A lot of things could have happened to show those nose dives, maybe this shot was taken during a time of some pool hopping

Pool hoppers never were at a Petahash level.