How often SERP Change

I found my site in 16 th page of google serp and later after some time it has come to 15th page and again to 16 th page.How this happens? can any one explain me?

 

Serps change all the time. Google recalculates their algorithms very often. New and less then trusted sites often go up and down in the serps. just changing from page 15 to 16 isn't that big a change, actually.

Nothing you can do about it except try and get better links.

 

Evry day hour they are changes ... fluctuations

 

A few days SERPs change. Sometimes just changed for some keywords, not all group.

 

almost every day SERPS change... because They have Different DC's.

 

Every day, just monitor your site from time to time.

 

As sites become higher ranked or lower ranked, your position fluctuates.

 

Yeah, monitoring your SERPS can be liking watching a yo-yo sometimes.

 

For some keywords changes are even more often if they are more competitive and a bunch of SEO people are targeting your keywords.

But yes, it changes all the time although some sites may be seen moving a lot more than others, but the SERPs just change all the time.

 

every day.. better to say every time..