Macbook battery health constantly changing??

[ncavs10]

I have a blackbook with a CD 2GHz processor and ive had it now for about 2 years. I regularly exercise my battery and its life has been fine until this year. It seems like every time i charge the battery according to istat pro my battery's health varies anywhere from as low as 44% to maybe about 87%.

Anyone experience anything like this or suggest anything i can do before buying a new battery?

 

[haxderek]

but do you notice an actual change in battery life?

 

[ncavs10]

yes, and its enough to make me notice that my battery dies quicker than normal.