COUNTING ERROR??????

my Alexa widgets that I used to delete and put it back again and again because I noticed there something wrong on their measurement or what ever they called it.I'm newbie but it goes on simple way of observing on how it appears on my blog.I started with 16 million plus figure then after 3 weeks it goes down to 8 million plus.Then weekly it went down but last month I saw it in desame figure as of today.I send messages to help/support group that maybe this numbers are not mine because my visitors keep on going to high numbers.Yesterday I'm happy that it was already 1,988,113 on traffic rank, it was also in site info widgets all of these numbers last 3 days.Today when I woke up opening my page again it goes back to 2,940, 794.I don't really understand this.Are you guys experiencing like this or did you noticed it? How these situation affect on my blog? Are these widgets really need to put on? What for? Please leave your comments regarding this ups and downs measurement of Alexa traffic rank and site info.
I am always appreciating all comments for my improvements.
thanks in advance.god bliss.