MBA battery capacity all over the place

[DP812]

My MBA has had "service battery" on it for years and I've ignored it because it still worked fine. But a few weeks ago, I kept having problems with the charge dropping down to zero so I downloaded coconutBattery and it said that my battery capacity was at 30%. I ordered a replacement battery but then about a week later, the capacity was suddenly at 50%. Now today, it's at 60%.

How does the battery's life keep going up?

 

[Mlrollin91]

Once the battery drops below 80% capacity it tends to jump all over the place for the rest of the battery's life. Below 80% its considered 'used up' and just becomes unstable. My MBA is flirting with 80%. It is at 700 charge cycles.