The footnote about Lewis Point Estimates is super interesting.
"Lewis Point Estimate Determined as Follows.
Maximum Liklihood Estimate (MLE)= x/n
where x=success, n=tries
For MLE<=0.5, use Wilson Method = (x+2)/(n+4)
For MLE Between 0.5 and 0.9, use MLE = x/n
For MLE>=0.9, use Laplace Method = (x+1)/(n+2)
Lewis, J. & Lauro, J., "Improving the Accuracy of Small-Sample
Estimates of Completion Rates", Journal of Usability Studies,
Issue 3, Vol. 1, May 2006, pp. 136-150."
"Lewis Point Estimate Determined as Follows.