I was tracking adsense with firefox extension throughout the day and it was stuck with one particular amount since last 6 hours. I didn't find it normal and removed the extension. Within few minutes my adsense stats gone up to double. I guess, adsense doesn't like to be checked very often (whether directly or through extensions). Check after 6-10 hours once.
As tempting as it is, checking stats is pretty pointless and non productive, the only difference checking 100s of times a day will make to your Adsense earnings is by the development time you will have lost checking how much you have made. That being said I'm having my best day ever and am now off to check again
Google has recently changed their reporting software so it keeps the stats for the entire duration of your session. That's done for the obvious reason of lowering the load on their database servers. Thus the stats will change only if you log out or close your browser or use specialized stats tools designed to work around that session limitation. Of course, the system-wide stats need to change in between sessions, too. Otherwise you'll see the same figures even if you logged out and in again. Having to log out and in again makes your stats checking time even less productive, so it would be best to develop a habit of checking them 2-4 times a day. This way you can catch it soon enough when Google disables your account Yeah, I've been reading too many of those "I got banned" messages lately. Having said that I admit I look at my stats software toolbar popup 200 times a day or more
My objective is to just keep myself busy enough that I don't have time to check. I do use the firefox extension, but it is not terribly up-to-date and doesn't cover everything.
Version 1.6.1 of Adsense Notifier extension for Firefox is available (and working fine): http://code.mincus.com/?p=3
I still find it hard to believe that people are so paranoid that they actually think that Google will penalize you for checking your stats too often. If you would read some threads here the stats were stuck for hours at a time the past few days so that is more than likely why your stats jumped the way it did.