But I think this really shows just how hard it is to make real money in the app store. You have been as successful as any of us could hope to be there, yet your peak bounce is $8k/day. This is nothing to sneeze at, of course, but chances are very high it will quickly taper off the way these bumps usually do. In comparison, a decent engineer can pull in $8k/month easily, month after month. So my guess is that over a year you will be lucky to make anywhere near what you could have made at a salaried job with the same effort, and you're probably in the top 1% of earners.
The independence and freedom the solo dev enjoys is certainly worth something, but if you're considering abandoning a salaried job for a crack at the app store market be advised that you're likely to pay a tremendous premium for that freedom.