My sites dropped alot

So you huys that are here alot, maybe you can help me with a good answer on this.
I have several websites and they have all very good ranking, I build backlinks, alot of do folow and articles and so on. for the past days I dont even see the ranking, that means the tool I use show up to 300 ranking but its not there, this have happend to me before and allways come back higher, but now im afriad since google changed the algorytmen, will they come back or are they gone, 1 webpage are in ault and the otheres are in realestate.

Keep backlinking, try to not use spamy backlinks, try your best to find not spammed high PR backlinks and your sites will come up.
If this takes more then 1 month change the content on the site and it will come back up.

If your backlinks is Good, then this sounds like to Google Dance, Give it a week or so, and you might be back better and stronger.

well my sites have been doing the dance before, but allways came up again stronger, but now they are realy far away, Iknow and what I have been reading here on the forum that I should keep on building and this is what I do.
I also have started to use a email service that helped me alot, I got 10 sales in one day, and that was awsome

You use only unique content ?

You did any recent link building campaing ?

What kind of links you used ?

Is all your sites affected ? What is the pattern between them ?

If all sites are affected,did you use google analitics,adsense,same host etc..

This is the main factors that cause change on serps: Content,Backlinks,Interlinked sites.

I do articles every day for the past 3 months, high pr for the last 6 monhts, and this is the first time i dont find them in top 300, they are not deindexed, but far down. i keep on building as i usualy do and hope they come back stronger soon.
I also use google analy for 1 page.
I have done this for several years now and theese sites are all aged...