what causes frequent changes in number of urls in site:search?

[Gemini23]

I am in the process of removing a number of urls from Google Search and am waiting for Google to remove them from the search results. I have submitted url removal in WMT. The urls are either 301 redirect or 404 - content removed.

About 3 times now the site:xyzexample.com shows 1,000 urls more than another - within the same day. There should only be about 1200 urls and currently more than 3,000 showing. Any suggestions why this fluctuation is happening? Different data centres providing the search results?

[aakk9999]

It could be a different data centre or it could be some bug on Google side.

I found that I get more accurate results when I use site: command in combination with inurl: command for more granular URL patterns, then I add these numbers up.