How often does google update their algo?

Anyone know if there is a particular frequency that google follows to update algos? My site was rock steady for month in slot # for a particular keyword, all of a sudden got bumped down to slot 5, was there for a few days, then back up to slot 4 for a few more days, then back to slot 3 now. This happens every once in a while, and while I can't tell how often, it's pretty consistent the way i get bounced back to 5 then work my way back up over a week or two. It just seems kind of weird.

I'm curious to see if it follows the algo updates. Anyone know or have a good guess?

Are you doing any work during this period on-site or via back links - are your competitors updating their content - do you even notice when they make a change - perhaps Big G is not the problem here, perhaps you have a 5-way fight for that No.1 spot.

They do when they do... there is no real rythme today.

I would assume that they are doing it all the time. Or at least turning the small knobs all the time.

Matt Cutts recently said in his blog updates and fine tuning to the algo happens a few times a week. Just shows how important it is to stay upto date with the changes.

I agree with the others above. In addition, keep in mind that changes in ranking positions do not need to result from an algo change. Crawling the web, picking up new links and reevaluating how relevant a page is for each query takes time and it is done continuously.
So the data you get from google is updated constantly (and there are different data centres each of which has slightly different data at a given time).

ya thanks i try to stay uptodate so i get better seo

I understand what you and everyone is saying, but i just find it odd that the pattern repeats itself exactly at intervals... I get kicked down to slot #5, they work my way back up to #3, often without making a single change to the page. I understand normal fluctuation, but to me, the same pattern repeating itself is not normal fluctuation. So I thought it might have something to do with the algo changes...

Nope Dear . Google is ver smart..never discloses anything related to updates, algorithm

Google won't reveal their secret. But you can feel that google is updating its algo if many sites are experiencing drop in rankings.

Fine tuning always happening sure. roll out of massive updates generally every quarter. Let's not confuse regular data-pushes and algos (the former happen almost daily by now). They are getting more efficient for the most part, however, that still doesn't explain -900 filter. I'm all for whatever filters you want, but make up your mind, don't do bi-monthly -900 for kicks.

Well Dazfree, I understand your points here.I think Google's alogorithm is getting complex day by day.By this I mean, the parameters required to rank in google high, is getting tougher and tougher day by day.So, war3rd suffered such kick backs from Google, without actually making any changes in the site!!

Wha I also find odd is that it's the same pattern over and over again, 3 to 5, back to 3....

Well, its really a question mark for all of us! May be ur site suffered 3-5 and again back to 3 due to application of same google algorithm...I would say stick to good SEO techniques and dnt bother too much about it. Be patient and in the mean time, gather good and qualitative backlinks for your site. Hope u will do well in coming days..thats all i can say buddy