What Goes Up Often Comes Down

If you ask me if I'm happy with my newly promoted PR from 0 to 4, I'd say yes I am but I'm worried that it will be demoted again. Today, Barbara told me that her PR went down again. Her PR was like a see-saw going up and down for the last few days, as with other bloggers too. Really don't know why it's so unstable and I wonder how Google ranks blogs. So I better make hay while the sun shines coz I never know when it will be gloomy again.