Who says they do? What are you going by? (I don't know for sure, I'm just asking what you're basing your question off of)
cscgal
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Google updates PR constantly because it wants to determine which sites are valuable or not. And I'm not a big fan of PR. The display PR is simply a rounded off value determined from a logarithmic scale that can be easily manipulated.
mrandrei
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Are you guys talking about the green bar in the Google toolbar? If so, it's meaningless :)
cscgal
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well, that's the process and everyday many site is born I think that's why Google update PR frequently.
mokmok69
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Yes, they do ... but, as mokmok pointed out, new pages are being created and deleted every single day, new links are being added and removed every day, so there's ALWAYS going to be flucation as pagerank is continuously created and deleted.
cscgal
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Google pr update is every three or fourth month
shivanikapoor
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completely agree with bob and cscgal, PR are meaningless, but they have much value for advertisers. Basically, bob is right, PR are done to find out the sites selling links. I have noticed after every update that many sites gets impact due to selling links. Selling links can hurt your site page rank on google.
Robdale
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